Biomechanical and Physiological Responses to 120 Min. of Soccer-Specific Exercise
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| Title: | Biomechanical and Physiological Responses to 120 Min. of Soccer-Specific Exercise |
|---|---|
| Language: | English |
| Authors: | Field, Adam (ORCID |
| Source: | Research Quarterly for Exercise and Sport. 2020 91(4):692-704. |
| Availability: | Routledge. Available from: Taylor & Francis, Ltd. 530 Walnut Street Suite 850, Philadelphia, PA 19106. Tel: 800-354-1420; Tel: 215-625-8900; Fax: 215-207-0050; Web site: http://www.tandf.co.uk/journals |
| Peer Reviewed: | Y |
| Page Count: | 13 |
| Publication Date: | 2020 |
| Document Type: | Journal Articles Reports - Research |
| Education Level: | Higher Education Postsecondary Education |
| Descriptors: | Biomechanics, Exercise Physiology, Metabolism, Athletes, Team Sports, Measurement Equipment, Test Reliability, Biochemistry, Correlation, Exercise, Fatigue (Biology), College Athletics, Dietetics |
| DOI: | 10.1080/02701367.2019.1698698 |
| ISSN: | 0270-1367 |
| Abstract: | Purpose: The purpose of the study is to investigate biomechanical and physiological responses to soccer-specific exercise incorporating an extra-time period (ET) and assess the test-retest reliability of these responses. Methods: Twelve soccer players performed 120 min of soccer-specific exercise. Tri-axial (PL[subscript Total]) and uni-axial PlayerLoad™ in the vertical (PL[subscript V]), anterior-posterior (PL[subscript A-P]), and medial-lateral (PL[subscript M-L]) planes were monitored using a portable accelerometer. Likewise, respiratory exchange ratio (RER) was recorded throughout exercise. At the end of each 15-min period, players provided differential ratings of perceived exertion for legs (RPE-L), breathlessness (RPE-B) and overall (RPE-O), and capillary samples were taken to measure blood lactate (BLa) concentrations. The soccer-specific exercise was completed twice within 7 days to assess reliability. Results: A main effect for time was identified for PL[subscript Total] (p = 0.045), PL[subscript V] (p = 0.002), PL[subscript A-P] (p = 0.011), RER (p = 0.001), RPE-L (p = 0.001), RPE-O (p = 0.003), and CMJ (p = 0.020). A significant increase in PL[subscript Total] (234 ± 34 au) and decrease in RER (0.87 ± 0.03) was evident during 105-120 versus 0-15 min (215 ± 25 au; p = 0.002 and 0.92 ± 0.02; p = 0.001). Coefficients of variations were <10% and Pearson's correlation coefficient demonstrated moderate-to-very strong (0.33-0.99) reliability for all PL variables, RPE-B, BLa, and RER. Conclusions: These results suggest that mechanical efficiency is compromised and an increased rate of lipolysis is observed as a function of exercise duration, particularly during ET. These data have implications for practitioners interested in fatigue-induced changes during ET. |
| Abstractor: | As Provided |
| Entry Date: | 2020 |
| Accession Number: | EJ1275443 |
| Database: | ERIC |
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| FullText | Links: – Type: pdflink Url: https://content.ebscohost.com/cds/retrieve?content=AQICAHj0k_4E0hTGH8RJwT4gCJyBsGNe_WN95AvKlDbXJGqwxwHVSXYoO8nljGkYUMSvngLsAAAA4zCB4AYJKoZIhvcNAQcGoIHSMIHPAgEAMIHJBgkqhkiG9w0BBwEwHgYJYIZIAWUDBAEuMBEEDIrSKRD9TaXh6ft0pwIBEICBmwGzdde8laY5uLUfdJBhmO6FrsetVRyH7li86g7kAiSJNFaEXcm13-JCh1A9-2lz-dNed9b7eWrHoCQ-SbqoysCOq4O3qXhIx7fqNc3HnrI0OKkCfmuk-CoVOAgf1baxusbL51NFPGpvtnl4IrJntEm8UyfdjqUAcnbhJrDlGJYjnAXkYTpcb4bjl6PrO2wM7ec4laBOK9mRQvt8 Text: Availability: 1 Value: <anid>AN0146972027;rqe01dec.20;2020Nov16.03:37;v2.2.500</anid> <title id="AN0146972027-1">Biomechanical and Physiological Responses to 120 Min. of Soccer-Specific Exercise </title> <p>Purpose: The purpose of the study is to investigate biomechanical and physiological responses to soccer-specific exercise incorporating an extra-time period (ET) and assess the test–retest reliability of these responses. Methods: Twelve soccer players performed 120 min of soccer-specific exercise. Tri-axial (PL&lt;sub&gt;Total&lt;/sub&gt;) and uni-axial PlayerLoad™ in the vertical (PL&lt;sub&gt;V&lt;/sub&gt;), anterior–posterior (PL&lt;sub&gt;A–P&lt;/sub&gt;), and medial–lateral (PL&lt;sub&gt;M–L&lt;/sub&gt;) planes were monitored using a portable accelerometer. Likewise, respiratory exchange ratio (RER) was recorded throughout exercise. At the end of each 15-min period, players provided differential ratings of perceived exertion for legs (RPE-L), breathlessness (RPE-B) and overall (RPE-O), and capillary samples were taken to measure blood lactate (BLa) concentrations. The soccer-specific exercise was completed twice within 7 days to assess reliability. Results: A main effect for time was identified for PL&lt;sub&gt;Total&lt;/sub&gt; (p = 0.045), PL&lt;sub&gt;V&lt;/sub&gt; (p = 0.002), PL&lt;sub&gt;A–P&lt;/sub&gt; (p = 0.011), RER (p = 0.001), RPE-L (p = 0.001), RPE-O (p = 0.003), and CMJ (p = 0.020). A significant increase in PL&lt;sub&gt;Total&lt;/sub&gt; (234 ± 34 au) and decrease in RER (0.87 ± 0.03) was evident during 105–120 versus 0–15 min (215 ± 25 au; p = 0.002 and 0.92 ± 0.02; p = 0.001). Coefficients of variations were &lt;10% and Pearson's correlation coefficient demonstrated moderate-to-very strong (0.33–0.99) reliability for all PL variables, RPE-B, BLa, and RER. Conclusions: These results suggest that mechanical efficiency is compromised and an increased rate of lipolysis is observed as a function of exercise duration, particularly during ET. These data have implications for practitioners interested in fatigue-induced changes during ET.</p> <p>Keywords: Football; PlayerLoad™; oxygen consumption; perceived exertion; fatigue; reliability</p> <p>Professional soccer players are reported to cover a total distance of 9–12 km during a typical 90-min match (Mohr, Krustrup, &amp; Bangsbo, [<reflink idref="bib30" id="ref1">30</reflink>]). This activity involves frequent changes of direction, periods of high-speed running (HS), and sprinting, as well as rapid accelerations and decelerations that may result in temporary fatigue (Stølen, Chamari, Castagna, &amp; Wisløff, [<reflink idref="bib42" id="ref2">42</reflink>]). This is evidenced by reductions in HS distances during the second half compared to the first half in Premier League matches, both with (Bradley et al., [<reflink idref="bib10" id="ref3">10</reflink>]) and without the ball (Di Salvo, Gregson, Atkinson, Tordoff, &amp; Drust, [<reflink idref="bib16" id="ref4">16</reflink>]). In recent years, researchers have investigated these responses during 120 min of soccer-specific exercise (i.e., with the addition of a 30-min extra-time [ET] period). This period of match-play is required in domestic and international tournaments when matches are tied at the end of 90 min. Notably, at the previous four FIFA World Cups, 36% of knockout phase matches have proceeded to ET with 50% at the 2014 tournament requiring 120 min of match-play (Harper, Fothergill, West, Stevenson, &amp; Russell, [<reflink idref="bib22" id="ref5">22</reflink>]).</p> <p>To date, observations across 120 min of soccer match-play demonstrate that distances covered, and the number of accelerations, decelerations, and number of HS sprint efforts performed are reduced in professional players during ET versus 90 min (Russell, Sparkes, Northeast, &amp; Kilduff, [<reflink idref="bib39" id="ref6">39</reflink>]; Winder, Russell, Naughton, &amp; Harper, [<reflink idref="bib47" id="ref7">47</reflink>]). Moreover, a reduction in the number of dribbling and passing actions in elite soccer players has been reported during the final 15 min of ET compared with a number of other time points during matches (Harper, West, Stevenson, &amp; Russell, [<reflink idref="bib24" id="ref8">24</reflink>]). However, it is unlikely that decreases in the number of actions are explained by a reduction in skill proficiency, rather, a fatigue-related compromised ability to be involved with build up play. In further support of this notion, increased neuromuscular fatigue (i.e., reduced muscle force production) has been observed during and following ET (Goodall et al., [<reflink idref="bib20" id="ref9">20</reflink>]). Furthermore, higher plasma glycerol, nonesterified fatty acids, and adrenaline as well as lower blood lactate (BLa) and glucose have been observed during ET, which is indicative of an increased rate of lipolysis (Stevenson et al., [<reflink idref="bib41" id="ref10">41</reflink>]). This change in energy pathway potentially explains the reductions in HS and sprint performance (Harper et al., [<reflink idref="bib23" id="ref11">23</reflink>]; Russell et al., [<reflink idref="bib39" id="ref12">39</reflink>]) as evidence suggests that the favorable energy pathway to fuel high-intensity exercise is glycogenolysis (Mohr, Krustrup, &amp; Bangsbo, [<reflink idref="bib31" id="ref13">31</reflink>]). These changes are notable as ET is typically played in important cup and tournaments, and indeed, matches often progress to or are decided during this period.</p> <p>Researchers have previously measured responses to 90 and 120 min of soccer using both match-play and simulations (Harper et al., [<reflink idref="bib23" id="ref14">23</reflink>]; Page, Marrin, Brogden, &amp; Greig, [<reflink idref="bib35" id="ref15">35</reflink>]; Russell et al., [<reflink idref="bib39" id="ref16">39</reflink>]). Whilst match-play provides high ecological validity, between match physical performance is highly variable (Carling, Bradley, McCall, &amp; Dupont, [<reflink idref="bib13" id="ref17">13</reflink>]) and logistical constraints limit physiological measurements during competitive games (Coutts, Rampinini, Marcora, Castagna, &amp; Impellizzeri, [<reflink idref="bib15" id="ref18">15</reflink>]). Therefore, simulating soccer match-play has been proposed as a feasible alternative which further reduces injury-risk by negating the physical contact associated with match-play (Page et al., [<reflink idref="bib35" id="ref19">35</reflink>]), which is responsible for ~70% of injuries (Aoki, O'Hata, Kohno, Morikawa, &amp; Seki, [<reflink idref="bib3" id="ref20">3</reflink>]). However to date, the Soccer Match Simulation (Russell, Rees, Benton, &amp; Kingsley, [<reflink idref="bib38" id="ref21">38</reflink>]) is the only reliable soccer-exercise stimulus over 120 min (Harper et al., [<reflink idref="bib23" id="ref22">23</reflink>]). This free-running soccer-specific exercise incorporates skill actions and changes of direction, although due to pacing, potentially fails to elicit a mechanistically valid fatigue-response inherent within treadmill-based protocols (Page et al., [<reflink idref="bib35" id="ref23">35</reflink>]). Furthermore, treadmill simulations eliminate self-pacing as periods of workload are standardized, and thus, changes in a given variable are likely fatigue-induced (Page et al., [<reflink idref="bib35" id="ref24">35</reflink>]). A validated motorized treadmill simulation has been used previously to investigate changes in physiological and biomechanical responses across 90 min of soccer-specific exercise (Page et al., [<reflink idref="bib35" id="ref25">35</reflink>]). This simulation has also shown to be valid over 120 min as distances covered (Winder et al., [<reflink idref="bib47" id="ref26">47</reflink>]) and number of sprints actions (Russell et al., [<reflink idref="bib39" id="ref27">39</reflink>]) are consistent with 120 min of actual-match-play. However, the test–retest reliability has not previously been assessed and thus there is scope to further investigate reliability of these responses over 120 min.</p> <p>Over recent years, assessments of within-match fatigue profiles have become increasingly common since the International Football Association Board approved the use of wearable technologies (e.g., accelerometers). A novel metric that has been proposed by Catapult Innovations as a measure of movement efficiency is that of PlayerLoad™ (PL) (Cormack, Mooney, Morgan, &amp; McGuigan, [<reflink idref="bib14" id="ref28">14</reflink>]). This parameter is defined as the instantaneous rate of acceleration across three planes of motion (i.e., vertical, anterior/posterior, and medial/lateral) and otherwise referred to as "jerk" (Nicolella, Torres-Ronda, Saylor, &amp; Schelling, [<reflink idref="bib33" id="ref29">33</reflink>]). Previously, changes in PL have been observed during the latter stages of a contemporary 90-min soccer simulation, indicating a fatigue-induced deterioration in movement efficiency (Page et al., [<reflink idref="bib35" id="ref30">35</reflink>]). These fatigue patterns are analogous with those of a match (Bradley et al., [<reflink idref="bib10" id="ref31">10</reflink>]) which can manifest through a reduced vertical stiffness in the lower extremities (detectable via changes in PL/jerk) (Oliver, Croix, Lloyd, &amp; Williams, [<reflink idref="bib34" id="ref32">34</reflink>]). The etiology of such changes may be a decreased neuromuscular control (Oliver et al., [<reflink idref="bib34" id="ref33">34</reflink>]), potentially compromising dynamic joint stability (Hughes &amp; Watkins, [<reflink idref="bib28" id="ref34">28</reflink>]). This could be owing to a reduced absorption capacity and increased stress response to soft tissues (Hughes &amp; Watkins, [<reflink idref="bib28" id="ref35">28</reflink>]), leading to impaired movement efficiency which suggests an increased load per distance covered (Barrett et al., [<reflink idref="bib7" id="ref36">7</reflink>]) and potential increased injury-risk. Furthermore, recent research suggests that exacerbated recovery following matches that proceed to ET (Winder et al., [<reflink idref="bib47" id="ref37">47</reflink>]) may predispose players to injury, especially during fixture congested microcyles (Silva et al., [<reflink idref="bib40" id="ref38">40</reflink>]). Possible risk factors for injury may involve lower limb muscle activity reductions and inhibited recovery kinetics, contributing to subsequent impeded movement quality whilst performing explosive and unaccustomed activities (Silva et al., [<reflink idref="bib40" id="ref39">40</reflink>]). Therefore, investigating changes in PL responses over 120 min may help elucidate whether recovery and injury-risk are impacted further by the additional duration and workload associated with ET.</p> <p>Whilst PL is a useful measure of external load, internal load (e.g., heart rate [HR] and rating of perceived exertion [RPE]) can provide important information pertaining to the impact of external stressors (Macpherson et al., [<reflink idref="bib29" id="ref40">29</reflink>]). Whilst increases in RPE have been observed during ET (Harper et al., [<reflink idref="bib23" id="ref41">23</reflink>]), differential RPE (d-RPE) responses have yet to be collected during this period. This method comprises three discrete scores for breathlessness (RPE-B), legs (RPE-L), and overall (RPE-O) loads (Borg, Borg, Larsson, Letzter, &amp; Sundblad, [<reflink idref="bib8" id="ref42">8</reflink>]). It has previously been employed as an approach to measuring exertional perceptions in soccer training (Macpherson et al., [<reflink idref="bib29" id="ref43">29</reflink>]) and 15–30-min post-soccer match-play (Barrett, McLaren, Spears, Ward, &amp; Weston, [<reflink idref="bib6" id="ref44">6</reflink>]). Given the demands of soccer are multifactorial, d-RPE may highlight distinct mechanisms of fatigue (Macpherson et al., [<reflink idref="bib29" id="ref45">29</reflink>]). For instance, RPE-L could quantify peripheral and mechanical loads which in turn inform the need for strength, power, or endurance work on specific working muscles (Weston, Siegler, Bahnert, McBrien, &amp; Lovell, [<reflink idref="bib45" id="ref46">45</reflink>]), whereas consistent high ratings of RPE-B could indicate a higher central and physiological load imposed on players, highlighting the need for aerobic training. Furthermore, as this measure is applied, sensitive, and easily administered (Macpherson et al., [<reflink idref="bib29" id="ref47">29</reflink>]), investigating d-RPE responses may assist in capturing multiple dimensions of exertion to facilitate understanding of player perceptions of load over 120 min of soccer-specific exercise.</p> <p>As mentioned previously, ET may cause a change in the predominant energy source used (i.e., endogenous carbohydrate [CHO] to fat) (Stevenson et al., [<reflink idref="bib41" id="ref48">41</reflink>]). However, previous researchers have used venous blood samples to estimate these changes in substrate utilization over 120 min (Stevenson et al., [<reflink idref="bib41" id="ref49">41</reflink>]), which is logistically difficult to measure during exercise. An alternative measure used to estimate relative proportions of CHO and fat oxidation is the respiratory exchange ratio (RER). This measure calculates volumes of gas exchange (i.e., O<subs>2</subs> uptake and CO<subs>2</subs> production) through use of a breath-by-breath system (Goedecke et al., [<reflink idref="bib19" id="ref50">19</reflink>]). Indeed, treadmill-based simulations offer a feasible approach to measuring RER as fixed periods of exercise intensity are required (Page et al., [<reflink idref="bib35" id="ref51">35</reflink>]). Likewise, using treadmills to apply fixed workloads is essential to assess changes in substrate throughout exercise when using the Wasserman, Hansen, Sue, Whipp, and Casaburi ([<reflink idref="bib44" id="ref52">44</reflink>]) equation to calculate RER. To date, researchers have yet to employ treadmill-based soccer simulations for ET and have thus far failed to calculate RER over 120 min. Therefore, using RER to estimate substrate utilization may provide practitioners and coaches with novel insight into CHO usage during ET and whether CHO intake must be modulated to spare endogenous CHO use and help maintain performance.</p> <p>To the authors' knowledge, no study has aimed to quantify biomechanical (i.e., PL) responses and measure substrate utilization (through RER) or collect d-RPE over 120 min of soccer-specific exercise. Therefore, this study aimed to investigate the biomechanical and physiological responses to 120 min of treadmill-based soccer-specific exercise. A secondary aim was to examine the test–retest reliability of these responses. We hypothesized that changes in PL would be indicative of a reduced efficiency and that a shift in RER values toward predominant use of fat oxidation would be observed during ET. In addition, it was postulated that d-RPE would increase as a function of exercise duration.</p> <hd id="AN0146972027-2">Materials and methods</hd> <p></p> <hd id="AN0146972027-3">Participants and experimental authorization</hd> <p>University-standard (<emph>n</emph> = 6) and semiprofessional (<emph>n</emph> = 6) outfield soccer players (age: 21.3 ± 2.9 years, stature: 178.5 ± 7.1 cm, mass: 70.42 ± 8.47 kg, maximal oxygen uptake [</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;x&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> ]: 56.58 ± 7.23 ml kg<sups>−1</sups> min<sups>−1</sups>, max HR: 199 ± 3 b min<sups>−1</sups>) with two or more years of soccer experience were recruited for participation. Exclusion criteria specified the diagnosis of lower limb musculoskeletal injury within the preceding 6 months, any medical condition affecting participation following completion of a medical screening questionnaire and a</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;x&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;mo&gt;&amp;#8804;&lt;/mo&gt;&lt;mn&gt;48.5&lt;/mn&gt;&lt;mspace width="thinmathspace" /&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;l&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mspace width="thinmathspace" /&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;&amp;#8722;&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;mspace width="thinmathspace" /&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;i&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;&amp;#8722;&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> , consistent with previous ET literature (Stevenson et al., [<reflink idref="bib41" id="ref53">41</reflink>]). Furthermore, participants were asked to refrain from strenuous exercise 48 h prior to testing. Institutional ethical approval was granted to allow the undertaking of research and written informed consent was obtained from participants prior to data collection.</p> <hd id="AN0146972027-4">Preliminary visit and familiarization trials</hd> <p>Participants attended the laboratory on four separate occasions. The preliminary visit (first visit) was used to assess</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;x&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> , once body mass and stature were determined (DPS-Promatic srl via Edison 21 47122, Forlì, Italy). A graded ramp test was completed until volitional exhaustion, which commenced at 10 km h<sups>−1</sups>, increasing by 1 km h<sups>−1</sups> every 30 s, until 17 km h<sups>−1</sups> was reached, at which point the gradient was increased by 0.5% at each 30 s interval. A 72-h period then separated the first visit from the familiarization trial (second visit). This visit involved a full habituation of all experimental procedures including the full 120 min of soccer-specific exercise, and the completion of a standardized, treadmill-based warm-up (~10 min). This comprised intermittent changes in speeds and a dynamic stretching sequence as dynamic stretching has acute ergogenic effects on sprint and jump performance versus static stretching (Needham, Morse, &amp; Degens, [<reflink idref="bib32" id="ref54">32</reflink>]). Thereafter, main trial 1 (third visit) was performed, followed by main trial two (fourth visit). The familiarization and both main trials were interspersed by 7 days to ensure full recovery. Identical procedures were followed for main trials one and two to assess the reliability of the mechanical and physiological responses and all other data are presented from main trial 2.</p> <hd id="AN0146972027-5">Main trial procedures</hd> <p>Participants were asked to record and replicate dietary intake for both main trials commencing 24 h prior until completion of exercise. Both main trials were conducted at the same time of day to minimize the effects of circadian variation. Upon arrival at the laboratory, a mid-flow urine sample was provided to measure urine osmolality (Osmocheck, Vitech Scientific, West Sussex, UK). A blood sample was then taken at rest followed by an assessment of body mass and stature. The warm-up, as reported earlier, was completed, and 200 ml of water was consumed. Measurements of countermovement jump height (CMJ) proceeded the warm-up, followed by a 5-min passive rest period. The quantity of water administered was standardized and provided at half-time (HT; 500 ml), full time (FT; 300 ml), and during the 2-min interval (200 ml) separating ET as per previous investigations (Harper et al., [<reflink idref="bib23" id="ref55">23</reflink>]). Assessments of CMJ and body mass were taken upon completion, immediately followed by an assessment of urine osmolality to determine hydration status; euhydration was accepted as &lt;600 mOsm kg<sups>−1</sups> (Hillman et al., [<reflink idref="bib25" id="ref56">25</reflink>]). Urine-corrected mass changes were calculated for body mass assessment.</p> <hd id="AN0146972027-6">Soccer simulation</hd> <p>A modified version of 90 min of soccer-specific exercise (Page et al., [<reflink idref="bib35" id="ref57">35</reflink>]) was performed on a motorized treadmill (h/p/cosmos pulsar® 3p: h/p/cosmos sports &amp; medical GmBH, Nussdorf, Germany). It comprised two 45-min halves interspersed by a 15-min passive recovery break (HT), followed by a 5-min passive rest period, and a further two 15-min periods (ET), separated by 2-min passive recovery. Similar to previous research (Harper et al., [<reflink idref="bib23" id="ref58">23</reflink>]), the soccer-specific exercise was performed in 15-min blocks (with data assessed likewise). The changes in speed were set at the treadmill limit (1.39 m s<sups>−2</sups>) and players reached maximal speeds of 25 km h<sups>−1</sups> during the soccer-specific exercise (Figure 1). This soccer-specific exercise was designed to simulate the durations, intensities, and the velocity profile of match-play based on previous notational analyses (Mohr et al., [<reflink idref="bib30" id="ref59">30</reflink>]). The participants covered a distance of 16.26 km (similar to actual match-play; Winder et al., [<reflink idref="bib47" id="ref60">47</reflink>]) during the soccer-specific exercise with blood capillary samples, and d-RPE provided at the end of each 15-min bout of activity. Mean values for RER,</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> , HR, and PL data were taken as an average across each 15-min block of exercise.</p> <p>Graph: Figure 1. A schematic of an individual 15-min bout of the soccer-specific exercise</p> <hd id="AN0146972027-7">Experimental measures</hd> <p>Respiratory flow volumes were recorded continuously throughout the trial using a volume transducer (Triple® V, Cortex, Germany) and breath-by-breath automated gas analysis system (Metamax® 3B-R2, Cortex, Germany). Thereafter, individual mean (</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> ) values were expressed as average O<subs>2</subs> intake across each 15-min bout and the highest value reached was defined as</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;p&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> . Additionally, RER was calculated from the proportion of CO<subs>2</subs> produced and O<subs>2</subs> consumed through use of the manufacturer software equation (Metasoft®Studio Cortex, Germany; Wasserman et al., [<reflink idref="bib44" id="ref61">44</reflink>]) and defined as the mean over each 15-min bout of the trial.</p> <p>The treadmill automatically paused at the end of each 15-min block of exercise and a finger-tip blood capillary sample was taken before the treadmill manually resumed and sample was later analyzed for BLa (Biosen C-Line; EKF-diagnostic GmBH, Cardiff, Wales). In addition, d-RPE was provided through use of the Borg 15-point (6–20) linear scale (Borg, [<reflink idref="bib9" id="ref62">9</reflink>]) and participants were asked to differentiate between RPE-L, RPE-B, and RPE-O for each 15-min block of activity. To eliminate order effects, these values were collected in a counterbalanced order. CMJ height was measured using two portable photoelectric cells (Optojump, Italy) and was calculated using Optojump software. The jumps were separated by a 10-s passive rest interval for each of five respective time points (rest, post-HT, pre-second-half, 90, and 120 min). Participants were instructed to jump with hands on hips to nullify the influence of momentum; the mean of three jumps were presented for analysis.</p> <p>A portable accelerometer (Kionix KX94, Kionix, Ithaca, New York, USA), housed inside a GPS unit (OptimEye S5, Catapult Innovations, Scoresby, Australia), was used to measure tri-axial PL (PL<subs>Total</subs>) at a sampling frequency of 100 Hz. Participants were assigned the same unit for each trial to avoid inter-unit variation, as the Catapult OptimEye S5 device has been shown to possess high intra-unit reliability, yet inconsistent inter-unit reliability (Nicolella et al., [<reflink idref="bib33" id="ref63">33</reflink>]). A tight-fitted neoprene garment was worn to secure the device, housed in-between the scapulae to limit movement artifacts. A HR sensor (Polar H10, Polar USA, United States) was synchronized with the GPS unit, attached directly to the vest via a snap fastener and worn inferior to the sternum to quantify both mean (HR<subs>mean</subs>) and max (HR<subs>max</subs>) HR values; HR<subs>max</subs> was defined as the peak value recorded during a given 15-min exercise bout. Uni-axial PlayerLoad<sups>TM</sups> was determined for each movement plane (vertical [PL<subs>V</subs>], anterior–posterior [PL<subs>A–P</subs>], and medial–lateral [PL<subs>M–L</subs>]). Participant PL<subs>Total</subs> values were derived from the summation of the aforementioned planes of motion. The relative contributions of the uni-axial vectors were calculated (PL<subs>V%</subs>, PL<subs>A–P%</subs>, and PL<subs>M–L%</subs>) for the percentage contributions to PL<subs>Total</subs>. All PL data were expressed as arbitrary units (au) and defined across each 15-min period of soccer exercise.</p> <hd id="AN0146972027-8">Statistical analyses</hd> <p>Data were analyzed using Statistical Package for the Social Sciences (IBM SPSS Statistics 24 for Windows; SPSS Inc., Chicago, IL, USA). Statistical significance was set at <emph>p</emph> ≤ 0.05 prior to analyses. All data were expressed as mean ± standard deviation, unless indicated otherwise. An a priori power analysis (GPower v3.1; Germany) deemed a sufficient sample size of 11 based on ≥80% power (1 − <emph>β</emph>), an alpha (<emph>α</emph>) of 0.05, and a medium effect size (ES) (<emph>d</emph> = 0.5) based on previous PL<subs>Total</subs> data (Page et al., [<reflink idref="bib35" id="ref64">35</reflink>]). Normal distribution of data and variance homogeneity between each 15-min interval were assessed using Shapiro–Wilk and a Levene's test, respectively.</p> <p>The data were divided into the following epochs: E1 (00:00–14:59 min), E2 (15:00–29:59 min), E3 (30:00–44:59 min), E4 (45:00–59:59 min), E5 (60:00–74:59 min), E6 (75:00–89:59 min), E7 (90:00–104:59 min), E8 (105:00–119:59 min). A repeated measures analysis of variance was used to determine the effect of time for each outcome. To control for family-wise error, <emph>post-hoc</emph> pairwise comparisons were applied using the Bonferroni correction method. In accordance with Hopkins ([<reflink idref="bib27" id="ref65">27</reflink>]), test–retest reliability was established using typical error and coefficient of variation (CV) for absolute reliability, and Pearson's correlation coefficient (<emph>r</emph>) for relative reliability. For CV, &lt;10% was accepted as good absolute reliability (Atkinson &amp; Nevill, [<reflink idref="bib4" id="ref66">4</reflink>]) and thresholds for <emph>r</emph> were considered moderate (0.3–0.5), strong (0.5–0.7), and very strong (&gt;0.7) (Hopkins, [<reflink idref="bib27" id="ref67">27</reflink>]). ESs were calculated using Cohen's <emph>d</emph> and were categorized as small (0.2), medium (0.5), and large (0.8) (Fritz, Morris, &amp; Richler, [<reflink idref="bib18" id="ref68">18</reflink>]).</p> <hd id="AN0146972027-9">Results</hd> <p>All participants were presented for data analysis, except for one participant for ventilatory values (owing to claustrophobia) and another for the blood analyses (due to hemophobia), albeit the remainder of their data was used.</p> <hd id="AN0146972027-10">PlayerLoad responses throughout 120 min of soccer exercise</hd> <p>As highlighted in Table 1, a main effect for time was observed for PL<subs>Total</subs> (<emph>p</emph> = 0.045) with <emph>post-hoc</emph> analyses revealing that values were higher during E8 compared to E1 (+9.9 ± 5.3%; <emph>p</emph> = 0.002; <emph>d</emph> = 0.8; Figure 2). Likewise, a main effect for time was found for PL<subs>V</subs> (<emph>p</emph> = 0.002) with significant increases observed during E8 (118 ± 19 au) compared to E1 (111 ± 16 au). In addition, main effects for time were identified for PL<subs>A–P</subs> (<emph>p</emph> = 0.011) with significance identified between E1 (53 ± 7 au) and E8 (60 ± 5 au). No time effects were established for PL<subs>M–L</subs> (<emph>p</emph> = 0.074), PL<subs>V%</subs> (<emph>p</emph> = 0.703), PL<subs>A–P%</subs> (<emph>p</emph> = 0.835), or PL<subs>M–L%</subs> (<emph>p</emph> = 0.463).</p> <p>Table 1. Biomechanical responses throughout 120 min of soccer-specific exercise (mean ± SD)</p> <p> <ephtml> &lt;table&gt;&lt;thead&gt;&lt;tr&gt;&lt;td /&gt;&lt;td&gt;Time&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;Variable&lt;/td&gt;&lt;td&gt;E1&lt;/td&gt;&lt;td&gt;E2&lt;/td&gt;&lt;td&gt;E3&lt;/td&gt;&lt;td&gt;E4&lt;/td&gt;&lt;td&gt;E5&lt;/td&gt;&lt;td&gt;E6&lt;/td&gt;&lt;td&gt;E7&lt;/td&gt;&lt;td&gt;E8&lt;/td&gt;&lt;/tr&gt;&lt;/thead&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;Total&lt;/sub&gt; (au)&lt;/td&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;208 &amp;#177; 27&lt;/td&gt;&lt;td&gt;213 &amp;#177; 28&lt;/td&gt;&lt;td&gt;217 &amp;#177; 28&lt;/td&gt;&lt;td&gt;217 &amp;#177; 27&lt;/td&gt;&lt;td&gt;219 &amp;#177; 26&lt;/td&gt;&lt;td&gt;220 &amp;#177; 25&lt;/td&gt;&lt;td&gt;225 &amp;#177; 22&lt;/td&gt;&lt;td&gt;227 &amp;#177; 23&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;215 &amp;#177; 25&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;216 &amp;#177; 23&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;220 &amp;#177; 22&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;226 &amp;#177; 27&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;226 &amp;#177; 24&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;229 &amp;#177; 25&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;230 &amp;#177; 23&lt;sup&gt;abc&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;234 &amp;#177; 24&lt;sup&gt;abcdef&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;209 &amp;#177; 25&lt;/td&gt;&lt;td&gt;212 &amp;#177; 24&lt;/td&gt;&lt;td&gt;217 &amp;#177; 24&lt;/td&gt;&lt;td&gt;220 &amp;#177; 26&lt;/td&gt;&lt;td&gt;220 &amp;#177; 24&lt;/td&gt;&lt;td&gt;222 &amp;#177; 24&lt;/td&gt;&lt;td&gt;226 &amp;#177; 22&lt;/td&gt;&lt;td&gt;229 &amp;#177; 23&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;5&lt;/td&gt;&lt;td&gt;4.7&lt;/td&gt;&lt;td&gt;4.3&lt;/td&gt;&lt;td&gt;4.1&lt;/td&gt;&lt;td&gt;3.7&lt;/td&gt;&lt;td&gt;2.8&lt;/td&gt;&lt;td&gt;3&lt;/td&gt;&lt;td&gt;3.2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.84*&lt;/td&gt;&lt;td&gt;0.86*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;td&gt;0.91*&lt;/td&gt;&lt;td&gt;0.95*&lt;/td&gt;&lt;td&gt;0.92*&lt;/td&gt;&lt;td&gt;0.91*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;11.05&lt;/td&gt;&lt;td&gt;10.28&lt;/td&gt;&lt;td&gt;9.5&lt;/td&gt;&lt;td&gt;9.1&lt;/td&gt;&lt;td&gt;8.06&lt;/td&gt;&lt;td&gt;6.15&lt;/td&gt;&lt;td&gt;6.67&lt;/td&gt;&lt;td&gt;7.44&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;V&lt;/sub&gt; (au)&lt;/td&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;110 &amp;#177; 19&lt;/td&gt;&lt;td&gt;112 &amp;#177; 21&lt;/td&gt;&lt;td&gt;112 &amp;#177; 21&lt;/td&gt;&lt;td&gt;113 &amp;#177; 21&lt;/td&gt;&lt;td&gt;113 &amp;#177; 21&lt;/td&gt;&lt;td&gt;113 &amp;#177; 21&lt;/td&gt;&lt;td&gt;116 &amp;#177; 19&lt;/td&gt;&lt;td&gt;116 &amp;#177; 20&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;111 &amp;#177; 16&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;111 &amp;#177; 16&lt;/td&gt;&lt;td&gt;113 &amp;#177; 15&lt;/td&gt;&lt;td&gt;116 &amp;#177; 20&lt;/td&gt;&lt;td&gt;115 &amp;#177; 18&lt;sup&gt;g&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;116 &amp;#177; 19&lt;/td&gt;&lt;td&gt;117 &amp;#177; 18&lt;/td&gt;&lt;td&gt;118 &amp;#177; 19&lt;sup&gt;a&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;110 &amp;#177; 17&lt;/td&gt;&lt;td&gt;111 &amp;#177; 18&lt;/td&gt;&lt;td&gt;112 &amp;#177; 18&lt;/td&gt;&lt;td&gt;115 &amp;#177; 20&lt;/td&gt;&lt;td&gt;114 &amp;#177; 19&lt;/td&gt;&lt;td&gt;115 &amp;#177; 19&lt;/td&gt;&lt;td&gt;116 &amp;#177; 18&lt;/td&gt;&lt;td&gt;117 &amp;#177; 19&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;4.9&lt;/td&gt;&lt;td&gt;5.5&lt;/td&gt;&lt;td&gt;5.7&lt;/td&gt;&lt;td&gt;4.3&lt;/td&gt;&lt;td&gt;4.1&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;2.2&lt;/td&gt;&lt;td&gt;2.4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.91*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;td&gt;0.91*&lt;/td&gt;&lt;td&gt;0.95*&lt;/td&gt;&lt;td&gt;0.96*&lt;/td&gt;&lt;td&gt;0.98*&lt;/td&gt;&lt;td&gt;0.98*&lt;/td&gt;&lt;td&gt;0.97*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;5.76&lt;/td&gt;&lt;td&gt;6.89&lt;/td&gt;&lt;td&gt;6.91&lt;/td&gt;&lt;td&gt;4.96&lt;/td&gt;&lt;td&gt;4.66&lt;/td&gt;&lt;td&gt;3.1&lt;/td&gt;&lt;td&gt;2.87&lt;/td&gt;&lt;td&gt;3.47&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;A&amp;#8211;P&lt;/sub&gt; (au)&lt;/td&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;52 &amp;#177; 8&lt;/td&gt;&lt;td&gt;54 &amp;#177; 7&lt;/td&gt;&lt;td&gt;55 &amp;#177; 7&lt;/td&gt;&lt;td&gt;55 &amp;#177; 8&lt;/td&gt;&lt;td&gt;57 &amp;#177; 7&lt;/td&gt;&lt;td&gt;58 &amp;#177; 7&lt;/td&gt;&lt;td&gt;58 &amp;#177; 7&lt;/td&gt;&lt;td&gt;60 &amp;#177; 7&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;53 &amp;#177; 7&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;53 &amp;#177; 7&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;55 &amp;#177; 7&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;56 &amp;#177; 8&lt;/td&gt;&lt;td&gt;57 &amp;#177; 6&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;58 &amp;#177; 6&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;59 &amp;#177; 6&lt;sup&gt;abc&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;60 &amp;#177; 5&lt;sup&gt;abcef&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;52 &amp;#177; 7&lt;/td&gt;&lt;td&gt;54 &amp;#177; 7&lt;/td&gt;&lt;td&gt;55 &amp;#177; 7&lt;/td&gt;&lt;td&gt;56 &amp;#177; 7&lt;/td&gt;&lt;td&gt;57 &amp;#177; 6&lt;/td&gt;&lt;td&gt;58 &amp;#177; 6&lt;/td&gt;&lt;td&gt;58 &amp;#177; 6&lt;/td&gt;&lt;td&gt;60 &amp;#177; 6&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;6&lt;/td&gt;&lt;td&gt;4.8&lt;/td&gt;&lt;td&gt;3.3&lt;/td&gt;&lt;td&gt;5&lt;/td&gt;&lt;td&gt;4.6&lt;/td&gt;&lt;td&gt;4.3&lt;/td&gt;&lt;td&gt;4&lt;/td&gt;&lt;td&gt;4.9&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.86*&lt;/td&gt;&lt;td&gt;0.88*&lt;/td&gt;&lt;td&gt;0.94*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;td&gt;0.88*&lt;/td&gt;&lt;td&gt;0.84*&lt;/td&gt;&lt;td&gt;0.89*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;3.11&lt;/td&gt;&lt;td&gt;2.62&lt;/td&gt;&lt;td&gt;1.87&lt;/td&gt;&lt;td&gt;2.62&lt;/td&gt;&lt;td&gt;2.45&lt;/td&gt;&lt;td&gt;2.27&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;2.3&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;M&amp;#8211;L&lt;/sub&gt; (au)&lt;/td&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;47 &amp;#177; 6&lt;/td&gt;&lt;td&gt;47 &amp;#177; 6&lt;/td&gt;&lt;td&gt;48 &amp;#177; 6&lt;/td&gt;&lt;td&gt;49 &amp;#177; 6&lt;/td&gt;&lt;td&gt;49 &amp;#177; 6&lt;/td&gt;&lt;td&gt;49 &amp;#177; 6&lt;/td&gt;&lt;td&gt;51 &amp;#177; 6&lt;/td&gt;&lt;td&gt;51 &amp;#177; 6&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;47 &amp;#177; 7&lt;sup&gt;fh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;48 &amp;#177; 7&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;49 &amp;#177; 7&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;50 &amp;#177; 7&lt;/td&gt;&lt;td&gt;50 &amp;#177; 7&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;50 &amp;#177; 7&lt;sup&gt;a&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;51 &amp;#177; 7&lt;sup&gt;bc&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;52 &amp;#177; 8&lt;sup&gt;abce&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;47 &amp;#177; 6&lt;/td&gt;&lt;td&gt;47 &amp;#177; 6&lt;/td&gt;&lt;td&gt;49 &amp;#177; 6&lt;/td&gt;&lt;td&gt;49 &amp;#177; 6&lt;/td&gt;&lt;td&gt;49 &amp;#177; 6&lt;/td&gt;&lt;td&gt;50 &amp;#177; 6&lt;/td&gt;&lt;td&gt;51 &amp;#177; 6&lt;/td&gt;&lt;td&gt;52 &amp;#177; 7&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;7.5&lt;/td&gt;&lt;td&gt;6.1&lt;/td&gt;&lt;td&gt;5.7&lt;/td&gt;&lt;td&gt;5.2&lt;/td&gt;&lt;td&gt;5.4&lt;/td&gt;&lt;td&gt;5.2&lt;/td&gt;&lt;td&gt;4.8&lt;/td&gt;&lt;td&gt;5.2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.75*&lt;/td&gt;&lt;td&gt;0.82*&lt;/td&gt;&lt;td&gt;0.84*&lt;/td&gt;&lt;td&gt;0.85*&lt;/td&gt;&lt;td&gt;0.85*&lt;/td&gt;&lt;td&gt;0.87*&lt;/td&gt;&lt;td&gt;0.89*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;3.5&lt;/td&gt;&lt;td&gt;2.85&lt;/td&gt;&lt;td&gt;2.79&lt;/td&gt;&lt;td&gt;2.58&lt;/td&gt;&lt;td&gt;2.6&lt;/td&gt;&lt;td&gt;2.61&lt;/td&gt;&lt;td&gt;2.44&lt;/td&gt;&lt;td&gt;2.65&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;V%&lt;/sub&gt;&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;53 &amp;#177; 3&lt;/td&gt;&lt;td&gt;52 &amp;#177; 3&lt;/td&gt;&lt;td&gt;52 &amp;#177; 3&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;52 &amp;#177; 3&lt;/td&gt;&lt;td&gt;52 &amp;#177; 3&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;52 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;td&gt;51 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;1.8&lt;/td&gt;&lt;td&gt;2.5&lt;/td&gt;&lt;td&gt;1.9&lt;/td&gt;&lt;td&gt;1.5&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;1.4&lt;/td&gt;&lt;td&gt;0.9&lt;/td&gt;&lt;td&gt;1.6&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.94*&lt;/td&gt;&lt;td&gt;0.88*&lt;/td&gt;&lt;td&gt;0.95*&lt;/td&gt;&lt;td&gt;0.96*&lt;/td&gt;&lt;td&gt;0.95*&lt;/td&gt;&lt;td&gt;0.98*&lt;/td&gt;&lt;td&gt;0.99*&lt;/td&gt;&lt;td&gt;0.99*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;0.95&lt;/td&gt;&lt;td&gt;1.34&lt;/td&gt;&lt;td&gt;1.05&lt;/td&gt;&lt;td&gt;0.82&lt;/td&gt;&lt;td&gt;1.09&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.47&lt;/td&gt;&lt;td&gt;0.77&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;A&amp;#8211;P%&lt;/sub&gt;&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;25 &amp;#177; 4&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 4&lt;/td&gt;&lt;td&gt;26 &amp;#177; 4&lt;/td&gt;&lt;td&gt;26 &amp;#177; 4&lt;/td&gt;&lt;td&gt;27 &amp;#177; 4&lt;/td&gt;&lt;td&gt;26 &amp;#177; 4&lt;/td&gt;&lt;td&gt;27 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;25 &amp;#177; 3&lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;sup&gt;a&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;25 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;td&gt;26 &amp;#177; 3&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;4.6&lt;/td&gt;&lt;td&gt;3.5&lt;/td&gt;&lt;td&gt;3.2&lt;/td&gt;&lt;td&gt;4.5&lt;/td&gt;&lt;td&gt;3.2&lt;/td&gt;&lt;td&gt;3.7&lt;/td&gt;&lt;td&gt;2.9&lt;/td&gt;&lt;td&gt;2.5&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.92*&lt;/td&gt;&lt;td&gt;0.95*&lt;/td&gt;&lt;td&gt;0.96*&lt;/td&gt;&lt;td&gt;0.95*&lt;/td&gt;&lt;td&gt;0.96*&lt;/td&gt;&lt;td&gt;0.97*&lt;/td&gt;&lt;td&gt;0.96*&lt;/td&gt;&lt;td&gt;0.98*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;1.05&lt;/td&gt;&lt;td&gt;0.85&lt;/td&gt;&lt;td&gt;0.79&lt;/td&gt;&lt;td&gt;1.02&lt;/td&gt;&lt;td&gt;0.82&lt;/td&gt;&lt;td&gt;0.87&lt;/td&gt;&lt;td&gt;0.79&lt;/td&gt;&lt;td&gt;0.68&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;PL&lt;sub&gt;M&amp;#8211;L%&lt;/sub&gt;&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;23 &amp;#177; 2&lt;/td&gt;&lt;td&gt;23 &amp;#177; &amp;#177; 2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 1&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 1&lt;/td&gt;&lt;td&gt;22 &amp;#177; 1&lt;/td&gt;&lt;td&gt;22 &amp;#177; 1&lt;/td&gt;&lt;td&gt;23 &amp;#177; 1&lt;/td&gt;&lt;td&gt;23 &amp;#177; 1&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;22 &amp;#177; 1&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;22 &amp;#177; 2&lt;/td&gt;&lt;td&gt;23 &amp;#177; 2&lt;/td&gt;&lt;td&gt;23 &amp;#177; 2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;5&lt;/td&gt;&lt;td&gt;4.9&lt;/td&gt;&lt;td&gt;4.1&lt;/td&gt;&lt;td&gt;3.5&lt;/td&gt;&lt;td&gt;3&lt;/td&gt;&lt;td&gt;2.8&lt;/td&gt;&lt;td&gt;2.3&lt;/td&gt;&lt;td&gt;1.9&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.46&lt;/td&gt;&lt;td&gt;0.56&lt;/td&gt;&lt;td&gt;0.71*&lt;/td&gt;&lt;td&gt;0.84*&lt;/td&gt;&lt;td&gt;0.88*&lt;/td&gt;&lt;td&gt;0.86*&lt;/td&gt;&lt;td&gt;0.94*&lt;/td&gt;&lt;td&gt;0.96*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;1.1&lt;/td&gt;&lt;td&gt;1.08&lt;/td&gt;&lt;td&gt;0.93&lt;/td&gt;&lt;td&gt;0.82&lt;/td&gt;&lt;td&gt;0.64&lt;/td&gt;&lt;td&gt;0.67&lt;/td&gt;&lt;td&gt;0.52&lt;/td&gt;&lt;td&gt;0.43&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt; </ephtml> </p> <p>1 <emph>Note</emph>. PL<subs>Total</subs> = Tri-axial playerload; PL<subs>V</subs> = vertical playerload; PL<subs>A–P</subs> = anterior/posterior playerload; PL<subs>M–L</subs> = medial/lateral playerload; PL<subs>V%</subs> = percentage contribution of vertical vector; PL<subs>A–P%</subs> = percentage contribution of anterior/posterior vector; PL<subs>M–L%</subs> = percentage contribution of medial/lateral vector; au = arbitrary units; CV = coefficient of variation (%); <emph>r</emph> = Pearson's correlation coefficient; TE = typical error; E1 = 00:00–14:59 min, E2 = 15:00–29:59 min, E3 = 30:00–44:59 min, E4 = 45:00–59:59 min, E5 = 60:00–74:59 min, E6 = 75:00–89:59 min, E7 = 90:00–104:59 min, and E8 = 105:00–119:59 min; mean = mean of both trial 1 and 2. Significant differences are only reported for trial 2.</p> <ulist> <item>2 <sups>a–h</sups>Denote significance from E1 to E8 (<emph>p</emph> ≤ 0.05), respectively.</item> <item>3 *Denotes significance for Pearson's correlation coefficient for specified time points between trials (<emph>p</emph> ≤ 0.05).</item> </ulist> <p>Graph: Figure 2. This graph shows the time history changes in PLTotal response throughout 120 min of soccer-specific exercise. Data are expressed as mean ± SD. aDenotes significant difference from E7 for PLTotal; bdenotes significant difference from E8 for PLTotal (both p ≤ 0.05)</p> <hd id="AN0146972027-11">Physiological and physical responses throughout 120 min of soccer exercise</hd> <p>Significant main effects for time were evident for RER (<emph>p = </emph>0.001) with decreases observed during E8 (0.87 ± 0.03 au) compared to E1 (0.92 ± 0.02 au). Additionally, HR<subs>mean</subs> demonstrated a main effect for time (<emph>p</emph> = 0.003), with differences identified between E3 (159 ± 16 b min<sups>−1</sups>) and E4 (152 ± 16 b min<sups>−1</sups>; <emph>p ≤ </emph>0.001), as well as E4 and E5 (159 ± 16 b min<sups>−1</sups>; <emph>p</emph> = 0.003). No main effects for time were observed for</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> (<emph>p</emph> = 0.407),</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;p&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> (<emph>p</emph> = 0.879), HR<subs>peak</subs> (<emph>p</emph> = 0.959), or BLa (<emph>p</emph> = 0.203). As outlined in Table 2, a main effect of time for both RPE-L (<emph>p</emph> = 0.001) and RPE-O (<emph>p</emph> = 0.003) was found. For RPE-L, a significant increase was detected from E1 (11 ± 1) to E8 (17 ± 1; <emph>p ≤ </emph>0.001) and a similar pattern was evident for RPE-O between E1 (11 ± 1) and E8 (17 ± 2; <emph>p ≤ </emph>0.001). No main effects were observed for RPE-B (<emph>p</emph> = 0.076). Main effects for time were established for CMJ (<emph>p</emph> = 0.020), however, <emph>post-hoc</emph> comparisons revealed no differences between time points.</p> <p>Table 2. Physiological responses throughout 120 min of soccer-specific exercise (mean ± SD)</p> <p> <ephtml> &lt;table&gt;&lt;thead&gt;&lt;tr&gt;&lt;td /&gt;&lt;td&gt;Time&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;Variable&lt;/td&gt;&lt;td&gt;E1&lt;/td&gt;&lt;td&gt;E2&lt;/td&gt;&lt;td&gt;E3&lt;/td&gt;&lt;td&gt;E4&lt;/td&gt;&lt;td&gt;E5&lt;/td&gt;&lt;td&gt;E6&lt;/td&gt;&lt;td&gt;E7&lt;/td&gt;&lt;td&gt;E8&lt;/td&gt;&lt;/tr&gt;&lt;/thead&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td&gt;RER (au)&lt;/td&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;0.93 &amp;#177; 0.03&lt;/td&gt;&lt;td&gt;0.92 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.92 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.90 &amp;#177; 0.03&lt;/td&gt;&lt;td&gt;0.91 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.89 &amp;#177; 0.03&lt;/td&gt;&lt;td&gt;0.88 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.88 &amp;#177; 0.03&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;0.92 &amp;#177; 0.02&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.92 &amp;#177; 0.02&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.91 &amp;#177; 0.02&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.89 &amp;#177; 0.02&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.90 &amp;#177; 0.02&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.89 &amp;#177; 0.02 &lt;sup&gt;h&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.87 &amp;#177; 0.02&lt;sup&gt;abcde&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;0.87 &amp;#177; 0.02&lt;sup&gt;abcdef&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;0.93 &amp;#177; 0.03&lt;/td&gt;&lt;td&gt;0.92 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.91 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.90 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.91 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.89 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.88 &amp;#177; 0.02&lt;/td&gt;&lt;td&gt;0.87 &amp;#177; 0.03&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;2.9&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;2.2&lt;/td&gt;&lt;td&gt;2.9&lt;/td&gt;&lt;td&gt;2.6&lt;/td&gt;&lt;td&gt;2.7&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;3.2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.33&lt;/td&gt;&lt;td&gt;0.47&lt;/td&gt;&lt;td&gt;0.42&lt;/td&gt;&lt;td&gt;0.65*&lt;/td&gt;&lt;td&gt;0.52&lt;/td&gt;&lt;td&gt;0.71*&lt;/td&gt;&lt;td&gt;0.72*&lt;/td&gt;&lt;td&gt;0.67*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;0.02&lt;/td&gt;&lt;td&gt;0.02&lt;/td&gt;&lt;td&gt;0.02&lt;/td&gt;&lt;td&gt;0.02&lt;/td&gt;&lt;td&gt;0.02&lt;/td&gt;&lt;td&gt;0.01&lt;/td&gt;&lt;td&gt;0.01&lt;/td&gt;&lt;td&gt;0.02&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;p id="ilm0009"&gt;&lt;graphic href="urqe&amp;#95;a&amp;#95;1698698&amp;#95;ilm0009.gif" content-type="Graph" /&gt;&lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover xmlns=""&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow xmlns=""&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/p&gt; (ml kg&lt;sup&gt;&amp;#8722;1&lt;/sup&gt; min&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;)&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;35 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;35 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;33 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;1.9&lt;/td&gt;&lt;td&gt;1.4&lt;/td&gt;&lt;td&gt;1.6&lt;/td&gt;&lt;td&gt;1.6&lt;/td&gt;&lt;td&gt;1.3&lt;/td&gt;&lt;td&gt;2.4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.78*&lt;/td&gt;&lt;td&gt;0.8*&lt;/td&gt;&lt;td&gt;0.85*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;td&gt;0.88*&lt;/td&gt;&lt;td&gt;0.87*&lt;/td&gt;&lt;td&gt;0.91*&lt;/td&gt;&lt;td&gt;0.67*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;2.07&lt;/td&gt;&lt;td&gt;2.06&lt;/td&gt;&lt;td&gt;1.88&lt;/td&gt;&lt;td&gt;1.41&lt;/td&gt;&lt;td&gt;1.59&lt;/td&gt;&lt;td&gt;1.63&lt;/td&gt;&lt;td&gt;1.3&lt;/td&gt;&lt;td&gt;2.35&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;p id="ilm0010"&gt;&lt;graphic href="urqe&amp;#95;a&amp;#95;1698698&amp;#95;ilm0010.gif" content-type="Graph" /&gt;&lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover xmlns=""&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow xmlns=""&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;p&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/p&gt; (ml kg&lt;sup&gt;&amp;#8722;1&lt;/sup&gt; min&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;)&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;35 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;35 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 5&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;33 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;td&gt;34 &amp;#177; 4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;4.4&lt;/td&gt;&lt;td&gt;4.1&lt;/td&gt;&lt;td&gt;5.7&lt;/td&gt;&lt;td&gt;5.4&lt;/td&gt;&lt;td&gt;5.5&lt;/td&gt;&lt;td&gt;6.3&lt;/td&gt;&lt;td&gt;3.2&lt;/td&gt;&lt;td&gt;4&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.85*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;td&gt;0.79*&lt;/td&gt;&lt;td&gt;0.79*&lt;/td&gt;&lt;td&gt;0.64*&lt;/td&gt;&lt;td&gt;0.29&lt;/td&gt;&lt;td&gt;0.85*&lt;/td&gt;&lt;td&gt;0.75*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;4.29&lt;/td&gt;&lt;td&gt;4.06&lt;/td&gt;&lt;td&gt;5.58&lt;/td&gt;&lt;td&gt;5.22&lt;/td&gt;&lt;td&gt;5.32&lt;/td&gt;&lt;td&gt;6.15&lt;/td&gt;&lt;td&gt;3.61&lt;/td&gt;&lt;td&gt;3.9&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;HR&lt;sub&gt;mean&lt;/sub&gt; (b min&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;)&lt;/td&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;154 &amp;#177; 17&lt;/td&gt;&lt;td&gt;157 &amp;#177; 19&lt;/td&gt;&lt;td&gt;160 &amp;#177; 21&lt;/td&gt;&lt;td&gt;152 &amp;#177; 18&lt;/td&gt;&lt;td&gt;157 &amp;#177; 22&lt;/td&gt;&lt;td&gt;157 &amp;#177; 22&lt;/td&gt;&lt;td&gt;160 &amp;#177; 20&lt;/td&gt;&lt;td&gt;163 &amp;#177; 18&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;150 &amp;#177; 13&lt;/td&gt;&lt;td&gt;154 &amp;#177; 16&lt;/td&gt;&lt;td&gt;159 &amp;#177; 16&lt;sup&gt;d&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;152 &amp;#177; 16&lt;sup&gt;ce&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;157 &amp;#177; 16&lt;sup&gt;d&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;157 &amp;#177; 16&lt;/td&gt;&lt;td&gt;157 &amp;#177; 15&lt;/td&gt;&lt;td&gt;159 &amp;#177; 16&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;152 &amp;#177; 15&lt;/td&gt;&lt;td&gt;155 &amp;#177; 17&lt;/td&gt;&lt;td&gt;159 &amp;#177; 18&lt;/td&gt;&lt;td&gt;152 &amp;#177; 17&lt;/td&gt;&lt;td&gt;157 &amp;#177; 18&lt;/td&gt;&lt;td&gt;157 &amp;#177; 19&lt;/td&gt;&lt;td&gt;158 &amp;#177; 17&lt;/td&gt;&lt;td&gt;161 &amp;#177; 17&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;3.2&lt;/td&gt;&lt;td&gt;6.2&lt;/td&gt;&lt;td&gt;8.8&lt;/td&gt;&lt;td&gt;8.6&lt;/td&gt;&lt;td&gt;8.9&lt;/td&gt;&lt;td&gt;7.2&lt;/td&gt;&lt;td&gt;7.7&lt;/td&gt;&lt;td&gt;5.7&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.91*&lt;/td&gt;&lt;td&gt;0.77*&lt;/td&gt;&lt;td&gt;0.56&lt;/td&gt;&lt;td&gt;0.53&lt;/td&gt;&lt;td&gt;0.59&lt;/td&gt;&lt;td&gt;0.75*&lt;/td&gt;&lt;td&gt;0.61*&lt;/td&gt;&lt;td&gt;0.77*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;9.18&lt;/td&gt;&lt;td&gt;9.08&lt;/td&gt;&lt;td&gt;12.84&lt;/td&gt;&lt;td&gt;12.18&lt;/td&gt;&lt;td&gt;13.01&lt;/td&gt;&lt;td&gt;10.68&lt;/td&gt;&lt;td&gt;11.61&lt;/td&gt;&lt;td&gt;8.74&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;HR&lt;sub&gt;peak&lt;/sub&gt; (b min&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;)&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;186 &amp;#177; 26&lt;/td&gt;&lt;td&gt;179 &amp;#177; 21&lt;/td&gt;&lt;td&gt;179 &amp;#177; 21&lt;/td&gt;&lt;td&gt;171 &amp;#177; 22&lt;/td&gt;&lt;td&gt;173 &amp;#177; 21&lt;/td&gt;&lt;td&gt;181 &amp;#177; 24&lt;/td&gt;&lt;td&gt;178 &amp;#177; 23&lt;/td&gt;&lt;td&gt;183 &amp;#177; 24&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;179 &amp;#177; 18&lt;/td&gt;&lt;td&gt;176 &amp;#177; 19&lt;/td&gt;&lt;td&gt;176 &amp;#177; 20&lt;/td&gt;&lt;td&gt;175 &amp;#177; 18&lt;/td&gt;&lt;td&gt;178 &amp;#177; 23&lt;/td&gt;&lt;td&gt;175 &amp;#177; 17&lt;/td&gt;&lt;td&gt;180 &amp;#177; 16&lt;/td&gt;&lt;td&gt;185 &amp;#177; 15&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;182 &amp;#177; 22&lt;/td&gt;&lt;td&gt;177 &amp;#177; 19&lt;/td&gt;&lt;td&gt;177 &amp;#177; 20&lt;/td&gt;&lt;td&gt;173 &amp;#177; 19&lt;/td&gt;&lt;td&gt;175 &amp;#177; 21&lt;/td&gt;&lt;td&gt;178 &amp;#177; 20&lt;/td&gt;&lt;td&gt;179 &amp;#177; 19&lt;/td&gt;&lt;td&gt;184 &amp;#177; 20&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;6&lt;/td&gt;&lt;td&gt;10.2&lt;/td&gt;&lt;td&gt;11&lt;/td&gt;&lt;td&gt;9.9&lt;/td&gt;&lt;td&gt;11.5&lt;/td&gt;&lt;td&gt;9.1&lt;/td&gt;&lt;td&gt;10.6&lt;/td&gt;&lt;td&gt;11.7&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.85&lt;/td&gt;&lt;td&gt;0.24&lt;/td&gt;&lt;td&gt;0.19&lt;/td&gt;&lt;td&gt;0.28&lt;/td&gt;&lt;td&gt;0.17&lt;/td&gt;&lt;td&gt;0.43&lt;/td&gt;&lt;td&gt;0.16&lt;/td&gt;&lt;td&gt;&amp;#8722;0.02&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;10.79&lt;/td&gt;&lt;td&gt;17.56&lt;/td&gt;&lt;td&gt;18.79&lt;/td&gt;&lt;td&gt;17&lt;/td&gt;&lt;td&gt;20.01&lt;/td&gt;&lt;td&gt;16.09&lt;/td&gt;&lt;td&gt;18.36&lt;/td&gt;&lt;td&gt;20.3&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;BLa (mmol L&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;)&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 1.0&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 1.0&lt;/td&gt;&lt;td&gt;2.1 &amp;#177; 0.6&lt;/td&gt;&lt;td&gt;2.2 &amp;#177; 1.2&lt;/td&gt;&lt;td&gt;2.5 &amp;#177; 1.2&lt;/td&gt;&lt;td&gt;2.6 &amp;#177; 1.2&lt;/td&gt;&lt;td&gt;2.2 &amp;#177; 1.0&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 1.0&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 0.9&lt;/td&gt;&lt;td&gt;2.9 &amp;#177; 1.5&lt;/td&gt;&lt;td&gt;2.7 &amp;#177; 1.2&lt;/td&gt;&lt;td&gt;2.3 &amp;#177; 0.9&lt;/td&gt;&lt;td&gt;3.0 &amp;#177; 1.3&lt;/td&gt;&lt;td&gt;3.8 &amp;#177; 2.7&lt;/td&gt;&lt;td&gt;2.7 &amp;#177; 0.9&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 1.1&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 0.9&lt;/td&gt;&lt;td&gt;2.6 &amp;#177; 1.2&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 0.9&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 1.0&lt;/td&gt;&lt;td&gt;2.8 &amp;#177; 1.2&lt;/td&gt;&lt;td&gt;3.3 &amp;#177; 2.1&lt;/td&gt;&lt;td&gt;2.6 &amp;#177; 0.9&lt;/td&gt;&lt;td&gt;2.4 &amp;#177; 1.0&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;0.8&lt;/td&gt;&lt;td&gt;0.9&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.5&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;1.8&lt;/td&gt;&lt;td&gt;0.6&lt;/td&gt;&lt;td&gt;0.6&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.6&lt;/td&gt;&lt;td&gt;0.41&lt;/td&gt;&lt;td&gt;0.12&lt;/td&gt;&lt;td&gt;0.46&lt;/td&gt;&lt;td&gt;0.89*&lt;/td&gt;&lt;td&gt;0.63*&lt;/td&gt;&lt;td&gt;0.32&lt;/td&gt;&lt;td&gt;0.59&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;0.77&lt;/td&gt;&lt;td&gt;0.94&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.51&lt;/td&gt;&lt;td&gt;0.67&lt;/td&gt;&lt;td&gt;1.78&lt;/td&gt;&lt;td&gt;0.57&lt;/td&gt;&lt;td&gt;0.6&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;RPE-L&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;/td&gt;&lt;td&gt;17 &amp;#177; 1&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;sup&gt;abcdefh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;17 &amp;#177; 1&lt;sup&gt;abcdefg&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;/td&gt;&lt;td&gt;17 &amp;#177; 1&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;1.9&lt;/td&gt;&lt;td&gt;1.8&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;1.6&lt;/td&gt;&lt;td&gt;1.5&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.64*&lt;/td&gt;&lt;td&gt;0.29&lt;/td&gt;&lt;td&gt;0.61*&lt;/td&gt;&lt;td&gt;0.39&lt;/td&gt;&lt;td&gt;0.61*&lt;/td&gt;&lt;td&gt;0.87*&lt;/td&gt;&lt;td&gt;0.64*&lt;/td&gt;&lt;td&gt;0.78*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;0.64&lt;/td&gt;&lt;td&gt;0.77&lt;/td&gt;&lt;td&gt;0.51&lt;/td&gt;&lt;td&gt;0.82&lt;/td&gt;&lt;td&gt;0.74&lt;/td&gt;&lt;td&gt;0.41&lt;/td&gt;&lt;td&gt;0.68&lt;/td&gt;&lt;td&gt;0.59&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;RPE-B&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 2&lt;/td&gt;&lt;td&gt;16 &amp;#177; 2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 2&lt;sup&gt;abcd&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;15 &amp;#177; 2&lt;sup&gt;abcd&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 2&lt;/td&gt;&lt;td&gt;16 &amp;#177; 2&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;1.8&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;1.5&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.75*&lt;/td&gt;&lt;td&gt;0.44&lt;/td&gt;&lt;td&gt;0.39&lt;/td&gt;&lt;td&gt;0.34&lt;/td&gt;&lt;td&gt;0.64*&lt;/td&gt;&lt;td&gt;0.68*&lt;/td&gt;&lt;td&gt;0.88*&lt;/td&gt;&lt;td&gt;0.86*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;0.55&lt;/td&gt;&lt;td&gt;0.84&lt;/td&gt;&lt;td&gt;0.77&lt;/td&gt;&lt;td&gt;0.96&lt;/td&gt;&lt;td&gt;0.82&lt;/td&gt;&lt;td&gt;0.84&lt;/td&gt;&lt;td&gt;0.76&lt;/td&gt;&lt;td&gt;0.86&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;RPE-O&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;16 &amp;#177; 1&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;sup&gt;gh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;15 &amp;#177; 2&lt;sup&gt;abcdefh&lt;/sup&gt;&lt;/td&gt;&lt;td&gt;17 &amp;#177; 2&lt;sup&gt;abcdefg&lt;/sup&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;11 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;12 &amp;#177; 1&lt;/td&gt;&lt;td&gt;13 &amp;#177; 1&lt;/td&gt;&lt;td&gt;14 &amp;#177; 1&lt;/td&gt;&lt;td&gt;15 &amp;#177; 1&lt;/td&gt;&lt;td&gt;16 &amp;#177; 1&lt;/td&gt;&lt;td&gt;17 &amp;#177; 1&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;2.1&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;1.4&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.84&lt;/td&gt;&lt;td&gt;0.17&lt;/td&gt;&lt;td&gt;0.22&lt;/td&gt;&lt;td&gt;0.9&lt;/td&gt;&lt;td&gt;0.45&lt;/td&gt;&lt;td&gt;0.84*&lt;/td&gt;&lt;td&gt;0.87*&lt;/td&gt;&lt;td&gt;0.9*&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;1.04&lt;/td&gt;&lt;td&gt;0.93&lt;/td&gt;&lt;td&gt;0.77&lt;/td&gt;&lt;td&gt;1.06&lt;/td&gt;&lt;td&gt;0.77&lt;/td&gt;&lt;td&gt;0.47&lt;/td&gt;&lt;td&gt;0.56&lt;/td&gt;&lt;td&gt;0.47&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td /&gt;&lt;td&gt;Pretrial&lt;/td&gt;&lt;td&gt;Post-HT&lt;/td&gt;&lt;td&gt;Pre-second half&lt;/td&gt;&lt;td&gt;90 min&lt;/td&gt;&lt;td&gt;120 min&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;CMJ (cm)&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 1&lt;/td&gt;&lt;td&gt;35.2 &amp;#177; 6.3&lt;/td&gt;&lt;td&gt;36.0 &amp;#177; 6.4&lt;/td&gt;&lt;td&gt;33.9 &amp;#177; 6.8&lt;/td&gt;&lt;td&gt;36.5 &amp;#177; 7.2&lt;/td&gt;&lt;td&gt;34.2 &amp;#177; 8.5&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Trial 2&lt;/td&gt;&lt;td&gt;35.4 &amp;#177; 7.1&lt;/td&gt;&lt;td&gt;36.5 &amp;#177; 7.4&lt;/td&gt;&lt;td&gt;34.6 &amp;#177; 7.9&lt;/td&gt;&lt;td&gt;36.8 &amp;#177; 7.7&lt;/td&gt;&lt;td&gt;34.3 &amp;#177; 8.4&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; Mean&lt;/td&gt;&lt;td&gt;35.3 &amp;#177; 6.4&lt;/td&gt;&lt;td&gt;36.2 &amp;#177; 6.6&lt;/td&gt;&lt;td&gt;34.3 &amp;#177; 7.1&lt;/td&gt;&lt;td&gt;36.6 &amp;#177; 7.1&lt;/td&gt;&lt;td&gt;34.2 &amp;#177; 8.1&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; CV (%)&lt;/td&gt;&lt;td&gt;0.8&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td&gt;1.1&lt;/td&gt;&lt;td&gt;0.9&lt;/td&gt;&lt;td&gt;0.7&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;italic&gt;r&lt;/italic&gt;&lt;/td&gt;&lt;td&gt;0.93*&lt;/td&gt;&lt;td&gt;0.94*&lt;/td&gt;&lt;td&gt;0.92*&lt;/td&gt;&lt;td&gt;0.99*&lt;/td&gt;&lt;td&gt;0.99*&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt; TE&lt;/td&gt;&lt;td&gt;1.96&lt;/td&gt;&lt;td&gt;1.98&lt;/td&gt;&lt;td&gt;2.27&lt;/td&gt;&lt;td&gt;0.8&lt;/td&gt;&lt;td&gt;1.04&lt;/td&gt;&lt;td /&gt;&lt;td /&gt;&lt;td /&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt; </ephtml> </p> <p>4 <emph>Note</emph>. RER = Respiratory exchange ratio;</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> = oxygen consumption; HR = heart rate; BLa = blood lactate; RPE = ratings of perceived exertion; RPE-L = RPE legs; RPE-B = RPE breathlessness; RPE-O = RPE overall; CMJ = countermovement jump height; au = arbitrary units; CV = coefficient of variation (%); <emph>r</emph> = Pearson's correlation coefficient; TE = typical error; E1 = 00:00–14:59 min, E2 = 15:00–29:59 min, E3 = 30:00–44:59 min, E4 = 45:00–59:59 min, E5 = 60:00–74:59 min, E6 = 75:00–89:59 min, E7 = 90:00–104:59 min, and E8 = 105:00–119:59 min; mean = mean of both trial 1 and 2. Significant differences are only reported for trial 2.</p> <ulist> <item>5 <sups>a–h</sups>Denote significant difference from E1 to E8 (<emph>p</emph> ≤ 0.05), respectively.</item> <item>6 *Denotes significance for Pearson's correlation coefficient for specified time points between trials (<emph>p</emph> ≤ 0.05).</item> </ulist> <p>No differences were detected for urine osmolality pre- (610 ± 132 mOsmoL kg<sups>−1</sups>) and post-trial (586 ± 135 mOsmoL kg<sups>−1</sups>; <emph>p</emph> = 0.985). Once urine-corrected, no changes in mass were identified from pre- (70.5 ± 8.8 kg) to post-trial (69.4 ± 8.5 kg; <emph>p</emph> = 0.928).</p> <hd id="AN0146972027-12">Reliability of biomechanical, physiological, and physical responses</hd> <p>All PL variables across all time points demonstrated a significant, very strong <emph>r</emph>, except for E1 and E2 for PL<subs>M–L%</subs>. All CVs were &lt;8% for all PL metrics across each time point (Table 1). For RER, moderate-to-very strong (<emph>r</emph> = 0.33–0.72) correlations were observed during each epoch of which E4, E6, E7, and E8 displayed significance (<emph>p</emph> ≤ 0.05). All CVs for RER were &lt;4% irrespective of time point. All time points for</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> and</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;p&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> (except for E8 for</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;m&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> ; E5 and E6 for</p> <p>Graph</p> <p> <ephtml> &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mo&gt;&amp;#729;&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;O&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant="normal"&gt;p&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;e&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;a&lt;/mi&gt;&lt;mi mathvariant="normal"&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; </ephtml> ) were &gt;0.70 (<emph>r</emph>), however, both demonstrated good (&lt;7%) CVs. For all epochs, the CV values were lower than 10% and strong-to-very strong (<emph>r</emph> = 0.51–0.75) relationships were found between trials for HR<subs>mean</subs>. Majority of CVs were &gt;10% for HR<subs>peak</subs> except E1, E4, and E6, and <emph>r</emph> was less than 0.3 for all epochs excluding E1 and E6. All CVs were &lt;3% for d-RPE values, and RPE-L and RPE-B demonstrated moderate-to-very strong (0.39–0.88) relationships for all time points except for RPE-L during E2 (0.29). Although RPE-O demonstrated moderate-to-very strong relationships for six out of eight time points (E1 and E4–E8; <emph>r</emph> = 0.45–0.9), all CVs were &lt;3% throughout the trial (refer to Table 2 for significance). Average CVs for CMJ were ~1%, and very strong, significant correlations were detected (&gt;0.9; <emph>r</emph>). CVs were &lt;10% for BLa and only two time points for <emph>r</emph> values were identified as significant (<emph>p</emph> ≤ 0.05).</p> <hd id="AN0146972027-13">Discussion</hd> <p>The aim of this study was to investigate the biomechanical and physiological responses to a 120 min of treadmill-based soccer-specific exercise. In accordance with our hypotheses, biomechanical performance was negatively impacted as a function of time, with further reductions in efficiency identified for PL<subs>Total</subs> during the final 30 min of exercise. Furthermore, increases in d-RPE and the rate of fat oxidation were observed during ET. Additionally, the test–retest reliability for most of the variables was moderate-to-very strong for relative reliability (i.e., <emph>r</emph>) and good for absolute reliability (i.e., CVs).</p> <p>To date, evidence suggests that the physical capacity of players is reduced during ET matches (Peñas, Dellal, Owen, &amp; Gómez-Ruano, [<reflink idref="bib36" id="ref69">36</reflink>]; Russell et al., [<reflink idref="bib39" id="ref70">39</reflink>]; Winder et al., [<reflink idref="bib47" id="ref71">47</reflink>]). However, caution should be applied when interpreting match-play observations as they do not account for contextual variables (Abbott, Brownlee, Harper, Naughton, &amp; Clifford, [<reflink idref="bib1" id="ref72">1</reflink>]) such as stoppages in play and altered tactical approaches. However, in the present study, the use of a treadmill simulation enabled the standardization of workload, thus allowing for any observed changes to be attributable to changes in a player's capacity to cope with the work rate, and as such, any observed changes in PL can be attributable to changes in movement efficiency rather than modifications to the activity and locomotion profile performed (Page et al., [<reflink idref="bib35" id="ref73">35</reflink>]).</p> <p>Page et al. ([<reflink idref="bib35" id="ref74">35</reflink>]) assessed PL responses across 90 min of treadmill-based, soccer-specific bouts of fixed, identical bouts of repeated activity. The authors reported increases in PL<subs>Total</subs>, concurrent with reductions in PL<subs>V%</subs> as a function of exercise duration. Similarly, previous match-play observations found a reduction in the vertical contribution of PL in Australian rules football players (Cormack et al., [<reflink idref="bib14" id="ref75">14</reflink>]). Consistent with the two studies above, our data suggest a similar temporal pattern, which, although not directly measured in the current study, may be indicative of an attempt to conserve energy by adjusting stride length or frequency, or both, which could in turn reduce running efficiency (Hobara et al., [<reflink idref="bib26" id="ref76">26</reflink>]). It appears that when fatigued, individual running patterns become biomechanically less efficient, which can cause additional stress to joints, tendons, and ligaments (Wilk, Nau, &amp; Valero, [<reflink idref="bib46" id="ref77">46</reflink>]). Furthermore, the modifications in vertical movement as seen in the present research have previously been associated with reductions in lower extremity stiffness (Buchheit, Gray, &amp; Morin, [<reflink idref="bib11" id="ref78">11</reflink>]).</p> <p>Although the relationship between stiffness and injury is not well established, it is believed that disproportionate levels of stiffness can lead to an increased injury-risk to the lower extremities (Butler, Crowell, &amp; Davis, [<reflink idref="bib12" id="ref79">12</reflink>]). From our data, it can be speculated that participants displayed less vertical displacement as a function of exercise duration, indicative of a reduced vertical stiffness and increased risk to soft tissues (Hughes &amp; Watkins, [<reflink idref="bib28" id="ref80">28</reflink>]). However, during matches, it is likely that in a subconscious attempt to avoid injury, players will reduce work rate, in turn impacting physical performance. In further support of a potential reduction in performance, impaired movement efficiency may also manifest in a reduced ability to maintain high intensity output, with this in turn reducing a team's ability to score goals. To support this suggestion, it has been suggested previously by Faude, Koch, and Meyer ([<reflink idref="bib17" id="ref81">17</reflink>]) that 45% of goals in the German Bundesliga were preceded with straight line sprints. Therefore, a reduced capacity during ET may result in fewer matches decided during this period and as such, preparing players for the additional 30-min duration associated with ET may reduce injury-risk and increase physical performance, ultimately increasing team success.</p> <p>Another novel feature of this study was the measurement of substrate utilization via gas analysis (i.e., RER) across 120 min of soccer-specific exercise. An RER of 1.0 indicates 100% CHO oxidation (i.e., glycolysis), whilst a value of 0.70 indicates 100% fatty acid oxidation (i.e., lipolysis), with 0.85 indicating an equal contribution. According to the current data and corresponding with previous ET research (Stevenson et al., [<reflink idref="bib41" id="ref82">41</reflink>]), players utilize both fat and CHO to fuel soccer exercise; however, fat oxidation increases during ET. Despite observing a shift in the direction of lipolysis and a downregulation in glycolysis, we are cognizant that our RER values during ET (0.87 au) suggest that CHO is still being utilized. Furthermore, as participants were less efficient (i.e., increased energy cost to produce the same activity) across bouts, it was surprising to find a ~29% reduction (although nonsignificant) in BLa concentrations between E6 and E7 (Figure 3). This further supports that glucose levels were potentially depleted and less was available to undergo biotransformation during ET as under anaerobic conditions, BLa is the final product of glycolysis.</p> <p>Graph: Figure 3. Mean RER and BLa concentrations across 120 min for each 15-min period of soccer-specific exercise. Data are expressed as mean ± SD. aDenotes significant difference from E7 for RER. bDenotes significant difference from E8 (p ≤ 0.05) for RER</p> <p>Prior to the main trials, participants in the current research were not required to consume a prematch meal as done in a previous investigation that has attempted to measure changes in substrate use (Stevenson et al., [<reflink idref="bib41" id="ref83">41</reflink>]). Therefore, this methodological discrepancy limits comparison between studies as participants in the current study may have completed exercise with lesser endogenous CHO at baseline. Furthermore, within-match CHO consumption is customary for soccer players (Anderson et al., [<reflink idref="bib2" id="ref84">2</reflink>]) and participants in the present research were limited to water intake. Evidence shows that exercising without exogenous CHO ingestion results in inherent increases in the oxidation of plasma free fatty acids (Gribok et al., [<reflink idref="bib21" id="ref85">21</reflink>]); however, this is largely influenced by exercise intensity and duration, among other factors (van Loon, Greenhaff, Constantin‐Teodosiu, Saris, &amp; Wagenmakers, [<reflink idref="bib43" id="ref86">43</reflink>]). Accordingly, further investigations examining the effect of CHO supplementation across 120 min of soccer-specific exercise are warranted.</p> <p>The present results indicate that the soccer-specific exercise imposed the most considerable load on RPE-L with scores reaching 17 ± 1 during ET, equating to the verbal anchor "very hard" according to the Borg scale. This finding is consistent with other work whereby RPE-L was highest during aerobic exercise (Borg et al., [<reflink idref="bib8" id="ref87">8</reflink>]) and ~30-min post-soccer match-play (Weston et al., [<reflink idref="bib45" id="ref88">45</reflink>]). However, given this study is the first to employ a within soccer-specific exercise approach to measuring d-RPE, it is difficult to compare our findings directly to other literature; therefore, this research may be used to inform future investigation that measures within-match changes in d-RPE. Furthermore, d-RPE typically increased as a function of exercise duration and was reliable between sessions (CV ≤ 2.1%). This suggests that d-RPE can be used to reliably assess internal load during soccer-specific exercise and may be a feasible tool to differentiate player exertion to assist in tailoring training programs (Macpherson et al., [<reflink idref="bib29" id="ref89">29</reflink>]).</p> <p>The test–retest responses to the current soccer-specific exercise simulation were moderate-to-strong. Previous convergent validity analysis by Barreira et al. ([<reflink idref="bib5" id="ref90">5</reflink>]) assessing two sessions of a free-running soccer match simulation demonstrated higher CVs for PL (14.5–24.5%) compared with the current study (PL<subs>Total</subs> = 2.8–5%). Considering the increased reliability of responses elicited during soccer exercise performed on treadmills, the current simulation may be preferable compared with free-running protocols such as the Soccer Match Simulation (Harper et al., [<reflink idref="bib23" id="ref91">23</reflink>]), especially if researchers have logistical issues, such as limited space. That said, skill performance is also impacted by exercise duration (Russell &amp; Kingsley, [<reflink idref="bib37" id="ref92">37</reflink>]) and it must be noted that treadmills are limited concerning the incorporation of technical actions. Therefore, if researchers are interested in assessing physical and physiological responses of players across 120 min of soccer-specific exercise, the current simulation may be desirable.</p> <p>Within the scope of the limitations, the findings of the current study add to an expanding body of literature that has thus far, failed to quantify the biomechanical demands and substrate usage estimated through the use of gaseous exchange during ET. To conclude, our data show a temporal shift in predominant energy pathway utilization (i.e., aerobic glycolysis to fat oxidation) during 120 min of soccer exercise. Likewise, changes in PL throughout 120 min of soccer-specific exercise were evident, with further fatigue-induced changes identified during ET.</p> <hd id="AN0146972027-14">What does this article add?</hd> <p>This study took a novel approach to investigating soccer-specific exercise over 120 min, that is, utilizing standardized periods of workload to assess fatigue responses. Based on these findings, we postulate that the reduced mechanical efficiency observed may hold fatigue-induced injury-risk implications for players during this period of match-play. However, the extent to which the additional demands associated with ET contribute to injury prevalence may be required through the longitudinal surveillance of soccer players. It is recommended that practitioners condition players to be able to cope with this additional workload associated with an additional 30 min to reduce potential injury occurrence, although the contemporary issue of fixture congestion may limit time to do so. Therefore, at which stage during the season this is developed and maintained must be considered. This research also confirms the importance of CHO consumption during soccer matches to maintain the glycolytic process, which may assist with offsetting the impact of fatigue. Finally, FIFA now authorize a fourth substitution during ET, and as such, utilizing replacements during this period may be efficacious to reduce the deleterious effect that fatigue may have on player performance.</p> <hd id="AN0146972027-15">Acknowledgments</hd> <p>The authors gratefully acknowledge the participants who willingly took part in the research.</p> <hd id="AN0146972027-16">Author contributions</hd> <p>AF, RMP, and LDH planned the study. AF, RN, and LDC conducted the data collection. AF, MH, SL, and LH completed data analysis. AF wrote the first draft and LDC, MH, RN RMP, and LDH reviewed the manuscript at various stages throughout the editing process and approved the final draft for publication.</p> <ref id="AN0146972027-17"> <title> References </title> <blist> <bibl id="bib1" idref="ref72" type="bt">1</bibl> <bibtext> Abbott, W., Brownlee, T. E., Harper, L. D., Naughton, R. J., &amp; Clifford, T. (2018). The independent effects of match location, match result and the quality of opposition on subjective wellbeing in under 23 soccer players: A case study. Research in Sports Medicine, 26 (3), 262 – 275. doi: 10.1080/15438627.2018.1447476</bibtext> </blist> <blist> <bibl id="bib2" idref="ref84" type="bt">2</bibl> <bibtext> Anderson, L., Orme, P., Di Michele, R., Close, G. L., Morgans, R., Drust, B., &amp; Morton, J. P. (2016). Quantification of training load during one-, two-and three-game week schedules in professional soccer players from the English Premier League: Implications for carbohydrate periodisation. Journal of Sports Sciences, 34 (13), 1250 – 1259. doi: 10.1080/02640414.2015.1106574</bibtext> </blist> <blist> <bibl id="bib3" idref="ref20" type="bt">3</bibl> <bibtext> Aoki, H., O'Hata, N., Kohno, T., Morikawa, T., &amp; Seki, J. (2012). A 15-year prospective epidemiological account of acute traumatic injuries during official professional soccer league matches in Japan. The American Journal of Sports Medicine, 40 (5), 1006 – 1014. doi: 10.1177/0363546512438695</bibtext> </blist> <blist> <bibl id="bib4" idref="ref66" type="bt">4</bibl> <bibtext> Atkinson, G., &amp; Nevill, A. M. (1998). Statistical methods for assessing measurement error (reliability) in variables relevant to sports medicine. Sports Medicine, 26 (4), 217 – 238. doi: 10.2165/00007256-199826040-00002</bibtext> </blist> <blist> <bibl id="bib5" idref="ref90" type="bt">5</bibl> <bibtext> Barreira, P., Robinson, M. A., Drust, B., Nedergaard, N., Raja Azidin, R. M. F., &amp; Vanrenterghem, J. (2017). Mechanical Player Load™ using trunk-mounted accelerometry in football: Is it a reliable, task-and player-specific observation? Journal of Sports Sciences, 35 (17), 1674 – 1681. doi: 10.1080/02640414.2016.1229015</bibtext> </blist> <blist> <bibl id="bib6" idref="ref44" type="bt">6</bibl> <bibtext> Barrett, S., McLaren, S., Spears, I., Ward, P., &amp; Weston, M. (2018). The influence of playing position and contextual factors on soccer players' match differential ratings of perceived exertion: A preliminary investigation. Sports, 6 (1), 13. doi: 10.3390/sports6010013</bibtext> </blist> <blist> <bibl id="bib7" idref="ref36" type="bt">7</bibl> <bibtext> Barrett, S., Midgley, A., Reeves, M., Joel, T., Franklin, E., Heyworth, R., &amp; Lovell, R. (2016). The within-match patterns of locomotor efficiency during professional soccer match play: Implications for injury risk? Journal of Science and Medicine in Sport, 19 (10), 810 – 815. doi: 10.1016/j.jsams.2015.12.514</bibtext> </blist> <blist> <bibl id="bib8" idref="ref42" type="bt">8</bibl> <bibtext> Borg, E., Borg, G., Larsson, K., Letzter, M., &amp; Sundblad, B. M. (2010). An index for breathlessness and leg fatigue. Scandinavian Journal of Medicine &amp; Science in Sports, 20 (4), 644 – 650. doi: 10.1111/j.1600-0838.2009.00985.x</bibtext> </blist> <blist> <bibl id="bib9" idref="ref62" type="bt">9</bibl> <bibtext> Borg, G. (1998). Borg's perceived exertion and pain scales. Champaign, IL: Human Kinetics.</bibtext> </blist> <blist> <bibtext> Bradley, P. S., Sheldon, W., Wooster, B., Olsen, P., Boanas, P., &amp; Krustrup, P. (2009). High-intensity running in English FA Premier League soccer matches. Journal of Sports Sciences, 27 (2), 159 – 168. doi: 10.1080/02640410802512775</bibtext> </blist> <blist> <bibtext> Buchheit, M., Gray, A., &amp; Morin, J. B. (2015). Assessing stride variables and vertical stiffness with GPS-embedded accelerometers: Preliminary insights for the monitoring of neuromuscular fatigue on the field. Journal of Sports Science &amp; Medicine, 14 (4), 698.</bibtext> </blist> <blist> <bibtext> Butler, R. J., Crowell, H. P., III, &amp; Davis, I. M. (2003). Lower extremity stiffness: Implications for performance and injury. Clinical Biomechanics, 18 (6), 511 – 517. doi: 10.1016/S0268-0033(03)00071-8</bibtext> </blist> <blist> <bibtext> Carling, C., Bradley, P., McCall, A., &amp; Dupont, G. (2016). Match-to-match variability in high-speed running activity in a professional soccer team. Journal of Sports Sciences, 34 (24), 2215 – 2223. doi: 10.1080/02640414.2016.1176228</bibtext> </blist> <blist> <bibtext> Cormack, S. J., Mooney, M. G., Morgan, W., &amp; McGuigan, M. R. (2013). Influence of neuromuscular fatigue on accelerometer load in elite Australian football players. International Journal of Sports Physiology and Performance, 8 (4), 373 – 378. doi: 10.1123/ijspp.8.4.373</bibtext> </blist> <blist> <bibtext> Coutts, A. J., Rampinini, E., Marcora, S. M., Castagna, C., &amp; Impellizzeri, F. M. (2009). Heart rate and blood lactate correlates of perceived exertion during small-sided soccer games. Journal of Science and Medicine in Sport, 12 (1), 79 – 84. doi: 10.1016/j.jsams.2007.08.005</bibtext> </blist> <blist> <bibtext> Di Salvo, V., Gregson, W., Atkinson, G., Tordoff, P., &amp; Drust, B. (2009). Analysis of high intensity activity in Premier League soccer. International Journal of Sports Medicine, 30 (03), 205 – 212. doi: 10.1055/s-0028-1105950</bibtext> </blist> <blist> <bibtext> Faude, O., Koch, T., &amp; Meyer, T. (2012). Straight sprinting is the most frequent action in goal situations in professional football. Journal of Sports Sciences, 30 (7), 625 – 631. doi: 10.1080/02640414.2012.665940</bibtext> </blist> <blist> <bibtext> Fritz, C. O., Morris, P. E., &amp; Richler, J. J. (2012). Effect size estimates: Current use, calculations, and interpretation. Journal of Experimental Psychology: General, 141 (1), 2. doi: 10.1037/a0024338</bibtext> </blist> <blist> <bibtext> Goedecke, J. H., Gibson, A. S. C., Grobler, L., Collins, M., Noakes, T. D., &amp; Lambert, E. V. (2000). Determinants of the variability in respiratory exchange ratio at rest and during exercise in trained athletes. American Journal of Physiology-Endocrinology and Metabolism, 279 (6), E1325 – E1334. doi: 10.1152/ajpendo.2000.279.6.E1325</bibtext> </blist> <blist> <bibtext> Goodall, S., Thomas, K., Harper, L. D., Hunter, R., Parker, P., Stevenson, E., ... Howatson, G. (2017). The assessment of neuromuscular fatigue during 120 min of simulated soccer exercise. European Journal of Applied Physiology, 117 (4), 687 – 697. doi: 10.1007/s00421-017-3561-9</bibtext> </blist> <blist> <bibtext> Gribok, A., Leger, J. L., Stevens, M., Hoyt, R., Buller, M., &amp; Rumpler, W. (2016). Measuring the short‐term substrate utilization response to high‐carbohydrate and high‐fat meals in the whole‐body indirect calorimeter. Physiological Reports, 4 (12), e12835. doi: 10.14814/phy2.12835</bibtext> </blist> <blist> <bibtext> Harper, L. D., Fothergill, M., West, D. J., Stevenson, E., &amp; Russell, M. (2016a). Practitioners' perceptions of the soccer extra-time period: Implications for future research. PLoS One, 11 (7), e0157687. doi: 10.1371/journal.pone.0157687</bibtext> </blist> <blist> <bibtext> Harper, L. D., Hunter, R., Parker, P., Goodall, S., Thomas, K., Howatson, G., &amp; Russell, M. (2016b). Test-retest reliability of physiological and performance responses to 120 minutes of simulated soccer match play. Journal of Strength and Conditioning Research, 30 (11), 3178 – 3186. doi: 10.1519/JSC.0000000000001400</bibtext> </blist> <blist> <bibtext> Harper, L. D., West, D. J., Stevenson, E., &amp; Russell, M. (2014). Technical performance reduces during the extra-time period of professional soccer match-play. PloS One, 9 (10), e110995. doi: 10.1371/journal.pone.0110995</bibtext> </blist> <blist> <bibtext> Hillman, A. R., Turner, M. C., Peart, D. J., Bray, J. W., Taylor, L., McNaughton, L. R., &amp; Siegler, J. C. (2013). A comparison of hyperhydration versus ad libitum fluid intake strategies on measures of oxidative stress, thermoregulation, and performance. Research in Sports Medicine, 21 (4), 305 – 317. doi: 10.1080/15438627.2013.825796</bibtext> </blist> <blist> <bibtext> Hobara, H., Inoue, K., Gomi, K., Sakamoto, M., Muraoka, T., Iso, S., &amp; Kanosue, K. (2010). Continuous change in spring-mass characteristics during a 400 m sprint. Journal of Science and Medicine in Sport, 13 (2), 256 – 261. doi: 10.1016/j.jsams.2009.02.002</bibtext> </blist> <blist> <bibtext> Hopkins, W. G. (2000). Measures of reliability in sports medicine and science. Sports Medicine, 30 (1), 1 – 15. doi: 10.2165/00007256-200030010-00001</bibtext> </blist> <blist> <bibtext> Hughes, G., &amp; Watkins, J. (2008). Lower limb coordination and stiffness during landing from volleyball block jumps. Research in Sports Medicine, 16 (2), 138 – 154. doi: 10.1080/15438620802103999</bibtext> </blist> <blist> <bibtext> Macpherson, T. W., McLaren, S. J., Gregson, W., Lolli, L., Drust, B., &amp; Weston, M. (2019). Using differential ratings of perceived exertion to assess agreement between coach and player perceptions of soccer training intensity: An exploratory investigation. Journal of Sports Sciences, 37, 1 – 6.</bibtext> </blist> <blist> <bibtext> Mohr, M., Krustrup, P., &amp; Bangsbo, J. (2003). Match performance of high-standard soccer players with special reference to development of fatigue. Journal of Sports Sciences, 21 (7), 519 – 528. doi: 10.1080/0264041031000071182</bibtext> </blist> <blist> <bibtext> Mohr, M., Krustrup, P., &amp; Bangsbo, J. (2005). Fatigue in soccer: A brief review. Journal of Sports Sciences, 23 (6), 593 – 599. doi: 10.1080/02640410400021286</bibtext> </blist> <blist> <bibtext> Needham, R. A., Morse, C. I., &amp; Degens, H. (2009). The acute effect of different warm-up protocols on anaerobic performance in elite youth soccer players. The Journal of Strength &amp; Conditioning Research, 23 (9), 2614 – 2620. doi: 10.1519/JSC.0b013e3181b1f3ef</bibtext> </blist> <blist> <bibtext> Nicolella, D. P., Torres-Ronda, L., Saylor, K. J., &amp; Schelling, X. (2018). Validity and reliability of an accelerometer-based player tracking device. PLoS One, 13 (2), e0191823. doi: 10.1371/journal.pone.0191823</bibtext> </blist> <blist> <bibtext> Oliver, J. L., Croix, M. B. D. S., Lloyd, R. S., &amp; Williams, C. A. (2014). Altered neuromuscular control of leg stiffness following soccer-specific exercise. European Journal of Applied Physiology, 114 (11), 2241 – 2249. doi: 10.1007/s00421-014-2949-z</bibtext> </blist> <blist> <bibtext> Page, R. M., Marrin, K., Brogden, C. M., &amp; Greig, M. (2015). Biomechanical and physiological response to a contemporary soccer match-play simulation. The Journal of Strength &amp; Conditioning Research, 29 (10), 2860 – 2866. doi: 10.1519/JSC.0000000000000949</bibtext> </blist> <blist> <bibtext> Peñas, C. L., Dellal, A., Owen, A. L., &amp; Gómez-Ruano, M. Á. (2015). The influence of the extra-time period on physical performance in elite soccer. International Journal of Performance Analysis in Sport, 15 (3), 830 – 839. doi: 10.1080/24748668.2015.11868834</bibtext> </blist> <blist> <bibtext> Russell, M., &amp; Kingsley, M. (2011). Influence of exercise on skill proficiency in soccer. Sports Medicine, 41 (7), 523 – 539. doi: 10.2165/11589130-000000000-00000</bibtext> </blist> <blist> <bibtext> Russell, M., Rees, G., Benton, D., &amp; Kingsley, M. (2011). An exercise protocol that replicates soccer match-play. International Journal of Sports Medicine, 32 (07), 511 – 518. doi: 10.1055/s-0031-1273742</bibtext> </blist> <blist> <bibtext> Russell, M., Sparkes, W., Northeast, J., &amp; Kilduff, L. P. (2015). Responses to a 120 min reserve team soccer match: A case study focusing on the demands of extra time. Journal of Sports Sciences, 33 (20), 2133 – 2139. doi: 10.1080/02640414.2015.1064153</bibtext> </blist> <blist> <bibtext> Silva, J. R., Rumpf, M. C., Hertzog, M., Castagna, C., Farooq, A., Girard, O., &amp; Hader, K. (2018). Acute and residual soccer match-related fatigue: A systematic review and meta-analysis. Sports Medicine, 48 (3), 539 – 583. doi: 10.1007/s40279-017-0798-8</bibtext> </blist> <blist> <bibtext> Stevenson, E. J., Watson, A., Theis, S., Holz, A., Harper, L. D., &amp; Russell, M. (2017). A comparison of isomaltulose versus maltodextrin ingestion during soccer-specific exercise. European Journal of Applied Physiology, 117 (11), 2321 – 2333. doi: 10.1007/s00421-017-3719-5</bibtext> </blist> <blist> <bibtext> Stølen, T., Chamari, K., Castagna, C., &amp; Wisløff, U. (2005). Physiology of soccer. Sports Medicine, 35 (6), 501 – 536. doi: 10.2165/00007256-200535060-00004</bibtext> </blist> <blist> <bibtext> van Loon, L. J., Greenhaff, P. L., Constantin‐Teodosiu, D., Saris, W. H., &amp; Wagenmakers, A. J. (2001). The effects of increasing exercise intensity on muscle fuel utilisation in humans. The Journal of Physiology, 536 (1), 295 – 304. doi: 10.1111/j.1469-7793.2001.00295.x</bibtext> </blist> <blist> <bibtext> Wasserman, K., Hansen, J. E., Sue, D. L., Whipp, B. J., &amp; Casaburi, R. (1987). Principles of exercise testing and interpretation. Philadelphia, PA: Lea &amp; Febiger.</bibtext> </blist> <blist> <bibtext> Weston, M., Siegler, J., Bahnert, A., McBrien, J., &amp; Lovell, R. (2015). The application of differential ratings of perceived exertion to Australian Football League matches. Journal of Science and Medicine in Sport, 18 (6), 704 – 708. doi: 10.1016/j.jsams.2014.09.001</bibtext> </blist> <blist> <bibtext> Wilk, B. R., Nau, S., &amp; Valero, B. (2009). Physical therapy management of running injuries using an evidenced based functional approach. AMAA Journal, 22 (1), 5 – 7.</bibtext> </blist> <blist> <bibtext> Winder, N., Russell, M., Naughton, R., &amp; Harper, L. (2018). The impact of 120 minutes of match-play on recovery and subsequent match performance: A case report in professional soccer players. Sports, 6 (1), 22. doi: 10.3390/sports6010022</bibtext> </blist> </ref> <aug> <p>By Adam Field; Liam David Corr; Matthew Haines; Steve Lui; Robert Naughton; Richard Michael Page and Liam David Harper</p> <p>Reported by Author; Author; Author; Author; Author; Author; Author</p> </aug> <nolink nlid="nl1" bibid="bib30" firstref="ref1"></nolink> <nolink nlid="nl2" bibid="bib42" firstref="ref2"></nolink> <nolink nlid="nl3" bibid="bib10" firstref="ref3"></nolink> <nolink nlid="nl4" bibid="bib16" firstref="ref4"></nolink> <nolink nlid="nl5" bibid="bib22" firstref="ref5"></nolink> <nolink nlid="nl6" bibid="bib39" firstref="ref6"></nolink> <nolink nlid="nl7" bibid="bib47" firstref="ref7"></nolink> <nolink nlid="nl8" bibid="bib24" firstref="ref8"></nolink> <nolink nlid="nl9" bibid="bib20" firstref="ref9"></nolink> <nolink nlid="nl10" bibid="bib41" firstref="ref10"></nolink> <nolink nlid="nl11" bibid="bib23" firstref="ref11"></nolink> <nolink nlid="nl12" bibid="bib31" firstref="ref13"></nolink> <nolink nlid="nl13" bibid="bib35" firstref="ref15"></nolink> <nolink nlid="nl14" bibid="bib13" firstref="ref17"></nolink> <nolink nlid="nl15" bibid="bib15" firstref="ref18"></nolink> <nolink nlid="nl16" bibid="bib38" firstref="ref21"></nolink> <nolink nlid="nl17" bibid="bib14" firstref="ref28"></nolink> <nolink nlid="nl18" bibid="bib33" firstref="ref29"></nolink> <nolink nlid="nl19" bibid="bib34" firstref="ref32"></nolink> <nolink nlid="nl20" bibid="bib28" firstref="ref34"></nolink> <nolink nlid="nl21" bibid="bib40" firstref="ref38"></nolink> <nolink nlid="nl22" bibid="bib29" firstref="ref40"></nolink> <nolink nlid="nl23" bibid="bib45" firstref="ref46"></nolink> <nolink nlid="nl24" bibid="bib19" firstref="ref50"></nolink> <nolink nlid="nl25" bibid="bib44" firstref="ref52"></nolink> <nolink nlid="nl26" bibid="bib32" firstref="ref54"></nolink> <nolink nlid="nl27" bibid="bib25" firstref="ref56"></nolink> <nolink nlid="nl28" bibid="bib27" firstref="ref65"></nolink> <nolink nlid="nl29" bibid="bib18" firstref="ref68"></nolink> <nolink nlid="nl30" bibid="bib36" firstref="ref69"></nolink> <nolink nlid="nl31" bibid="bib26" firstref="ref76"></nolink> <nolink nlid="nl32" bibid="bib46" firstref="ref77"></nolink> <nolink nlid="nl33" bibid="bib11" firstref="ref78"></nolink> <nolink nlid="nl34" bibid="bib12" firstref="ref79"></nolink> <nolink nlid="nl35" bibid="bib17" firstref="ref81"></nolink> <nolink nlid="nl36" bibid="bib21" firstref="ref85"></nolink> <nolink nlid="nl37" bibid="bib43" firstref="ref86"></nolink> <nolink nlid="nl38" bibid="bib37" firstref="ref92"></nolink> |
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| Header | DbId: eric DbLabel: ERIC An: EJ1275443 AccessLevel: 3 PubType: Academic Journal PubTypeId: academicJournal PreciseRelevancyScore: 0 |
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| Items | – Name: Title Label: Title Group: Ti Data: Biomechanical and Physiological Responses to 120 Min. of Soccer-Specific Exercise – Name: Language Label: Language Group: Lang Data: English – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Field%2C+Adam%22">Field, Adam</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0002-2600-6182">0000-0002-2600-6182</externalLink>)<br /><searchLink fieldCode="AR" term="%22Corr%2C+Liam+David%22">Corr, Liam David</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0001-7439-1372">0000-0001-7439-1372</externalLink>)<br /><searchLink fieldCode="AR" term="%22Haines%2C+Matthew%22">Haines, Matthew</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0002-6447-0306">0000-0002-6447-0306</externalLink>)<br /><searchLink fieldCode="AR" term="%22Lui%2C+Steve%22">Lui, Steve</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0002-4161-6181">0000-0002-4161-6181</externalLink>)<br /><searchLink fieldCode="AR" term="%22Naughton%2C+Robert%22">Naughton, Robert</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0002-9878-0396">0000-0002-9878-0396</externalLink>)<br /><searchLink fieldCode="AR" term="%22Page%2C+Richard+Michael%22">Page, Richard Michael</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0002-2916-8822">0000-0002-2916-8822</externalLink>)<br /><searchLink fieldCode="AR" term="%22Harper%2C+Liam+David%22">Harper, Liam David</searchLink> (ORCID <externalLink term="http://orcid.org/0000-0002-2089-4799">0000-0002-2089-4799</externalLink>) – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="SO" term="%22Research+Quarterly+for+Exercise+and+Sport%22"><i>Research Quarterly for Exercise and Sport</i></searchLink>. 2020 91(4):692-704. – Name: Avail Label: Availability Group: Avail Data: Routledge. Available from: Taylor & Francis, Ltd. 530 Walnut Street Suite 850, Philadelphia, PA 19106. Tel: 800-354-1420; Tel: 215-625-8900; Fax: 215-207-0050; Web site: http://www.tandf.co.uk/journals – Name: PeerReviewed Label: Peer Reviewed Group: SrcInfo Data: Y – Name: Pages Label: Page Count Group: Src Data: 13 – Name: DatePubCY Label: Publication Date Group: Date Data: 2020 – Name: TypeDocument Label: Document Type Group: TypDoc Data: Journal Articles<br />Reports - Research – Name: Audience Label: Education Level Group: Audnce Data: <searchLink fieldCode="EL" term="%22Higher+Education%22">Higher Education</searchLink><br /><searchLink fieldCode="EL" term="%22Postsecondary+Education%22">Postsecondary Education</searchLink> – Name: Subject Label: Descriptors Group: Su Data: <searchLink fieldCode="DE" term="%22Biomechanics%22">Biomechanics</searchLink><br /><searchLink fieldCode="DE" term="%22Exercise+Physiology%22">Exercise Physiology</searchLink><br /><searchLink fieldCode="DE" term="%22Metabolism%22">Metabolism</searchLink><br /><searchLink fieldCode="DE" term="%22Athletes%22">Athletes</searchLink><br /><searchLink fieldCode="DE" term="%22Team+Sports%22">Team Sports</searchLink><br /><searchLink fieldCode="DE" term="%22Measurement+Equipment%22">Measurement Equipment</searchLink><br /><searchLink fieldCode="DE" term="%22Test+Reliability%22">Test Reliability</searchLink><br /><searchLink fieldCode="DE" term="%22Biochemistry%22">Biochemistry</searchLink><br /><searchLink fieldCode="DE" term="%22Correlation%22">Correlation</searchLink><br /><searchLink fieldCode="DE" term="%22Exercise%22">Exercise</searchLink><br /><searchLink fieldCode="DE" term="%22Fatigue+%28Biology%29%22">Fatigue (Biology)</searchLink><br /><searchLink fieldCode="DE" term="%22College+Athletics%22">College Athletics</searchLink><br /><searchLink fieldCode="DE" term="%22Dietetics%22">Dietetics</searchLink> – Name: DOI Label: DOI Group: ID Data: 10.1080/02701367.2019.1698698 – Name: ISSN Label: ISSN Group: ISSN Data: 0270-1367 – Name: Abstract Label: Abstract Group: Ab Data: Purpose: The purpose of the study is to investigate biomechanical and physiological responses to soccer-specific exercise incorporating an extra-time period (ET) and assess the test-retest reliability of these responses. Methods: Twelve soccer players performed 120 min of soccer-specific exercise. Tri-axial (PL[subscript Total]) and uni-axial PlayerLoad™ in the vertical (PL[subscript V]), anterior-posterior (PL[subscript A-P]), and medial-lateral (PL[subscript M-L]) planes were monitored using a portable accelerometer. Likewise, respiratory exchange ratio (RER) was recorded throughout exercise. At the end of each 15-min period, players provided differential ratings of perceived exertion for legs (RPE-L), breathlessness (RPE-B) and overall (RPE-O), and capillary samples were taken to measure blood lactate (BLa) concentrations. The soccer-specific exercise was completed twice within 7 days to assess reliability. Results: A main effect for time was identified for PL[subscript Total] (p = 0.045), PL[subscript V] (p = 0.002), PL[subscript A-P] (p = 0.011), RER (p = 0.001), RPE-L (p = 0.001), RPE-O (p = 0.003), and CMJ (p = 0.020). A significant increase in PL[subscript Total] (234 ± 34 au) and decrease in RER (0.87 ± 0.03) was evident during 105-120 versus 0-15 min (215 ± 25 au; p = 0.002 and 0.92 ± 0.02; p = 0.001). Coefficients of variations were <10% and Pearson's correlation coefficient demonstrated moderate-to-very strong (0.33-0.99) reliability for all PL variables, RPE-B, BLa, and RER. Conclusions: These results suggest that mechanical efficiency is compromised and an increased rate of lipolysis is observed as a function of exercise duration, particularly during ET. These data have implications for practitioners interested in fatigue-induced changes during ET. – Name: AbstractInfo Label: Abstractor Group: Ab Data: As Provided – Name: DateEntry Label: Entry Date Group: Date Data: 2020 – Name: AN Label: Accession Number Group: ID Data: EJ1275443 |
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| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1080/02701367.2019.1698698 Languages: – Text: English PhysicalDescription: Pagination: PageCount: 13 StartPage: 692 Subjects: – SubjectFull: Biomechanics Type: general – SubjectFull: Exercise Physiology Type: general – SubjectFull: Metabolism Type: general – SubjectFull: Athletes Type: general – SubjectFull: Team Sports Type: general – SubjectFull: Measurement Equipment Type: general – SubjectFull: Test Reliability Type: general – SubjectFull: Biochemistry Type: general – SubjectFull: Correlation Type: general – SubjectFull: Exercise Type: general – SubjectFull: Fatigue (Biology) Type: general – SubjectFull: College Athletics Type: general – SubjectFull: Dietetics Type: general Titles: – TitleFull: Biomechanical and Physiological Responses to 120 Min. of Soccer-Specific Exercise Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Field, Adam – PersonEntity: Name: NameFull: Corr, Liam David – PersonEntity: Name: NameFull: Haines, Matthew – PersonEntity: Name: NameFull: Lui, Steve – PersonEntity: Name: NameFull: Naughton, Robert – PersonEntity: Name: NameFull: Page, Richard Michael – PersonEntity: Name: NameFull: Harper, Liam David IsPartOfRelationships: – BibEntity: Dates: – D: 01 M: 01 Type: published Y: 2020 Identifiers: – Type: issn-print Value: 0270-1367 Numbering: – Type: volume Value: 91 – Type: issue Value: 4 Titles: – TitleFull: Research Quarterly for Exercise and Sport Type: main |
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