Longitudinal Associations Between Changes in Physical Activity and Depressive Symptoms in Adulthood: The Young Finns Study. - Yang, Xiaolin; Hirvensalo, Mirja; Hintsanen, Mirka; Hintsa, Taina; Pulkki-Råback, Laura; Jokela, Markus; Telama, Risto; Tammelin, Tuija; Hutri-Kähönen, Nina; Viikari, Jorma; Raitakari, Olli (International Journal of Behavioral Medicine, 2014)