Higher antibody, but not cell-mediated, responses to vaccination in high physically fit elderly. - Keylock, K. Todd; Lowder, Thomas; Leitbeit, Kurt A.; Cook, Marc; Mariani, Rachel A.; Ross, Kristine; Kim, Kijin; Chapman-novakofski, Karen; McAuley, Edward; Woods, Jeffrey A. (Journal of Applied Physiology, 2007)