Search

Your search keyword '"Paterson, Donald H."' showing total 592 results
Start Over Author "Paterson, Donald H."
592 results on '"Paterson, Donald H."'

6. Physical activity guidelines and guides for Canadians: facts and future

Author

Tremblay, Mark S., Shephard, Roy J., Brawley, Lawrence R., Cameron, Christine, Craig, Cora Lynn, Duggan, Mary, Esliger, Dale W., Hearst, William, Hicks, Audrey, Janssen, Ian, Katzmarzyk, Peter T., Latimer, Amy E., Ginis, Kathleen A. Martin, McGuire, Ashlee, Paterson, Donald H., Sharratt, Michael, Spence, John C., Timmons, Brian, Warburton, Darren, Young, T. Kue, and Zehr, Lori

Published
2007

14. Response

Author

Keir, Daniel A., Fontana, Federico Y., Robertson, Taylor C., Murias, Juan M., Paterson, Donald H., Kowalchuk, John M., and Pogliaghi, Silvia

Published
2015
Full Text
View/download PDF

31. Prior heavy exercise elevates pyruvate dehydrogenase activity and muscle oxygenation and speeds [O.sub.2] uptake kinetics during moderate exercise in older adults

Author

Gurd, Brendon J., Peters, Sandra J., Heigenhauser, George J.F., LeBlanc, Paul J., Doherty, Timothy J., Paterson, Donald H., and Kowalchuk, John M.

Subjects
Exercise -- Physiological aspects, Exercise -- Genetic aspects, Exercise -- Research, Oxygen consumption -- Physiological aspects, Oxygen consumption -- Genetic aspects, Oxygen consumption -- Research, Pyruvate dehydrogenase complex -- Physiological aspects, Pyruvate dehydrogenase complex -- Genetic aspects, Biological sciences
Abstract

The adaptation of pulmonary oxygen uptake (V[O.sub.2p]) kinetics during the transition to moderate-intensity exercise is slowed in older compared with younger adults; however, this response is faster following a prior bout of heavy-intensity exercise. We have examined V[O.sub.2p] kinetics, pyruvate dehydrogenase (PDH) activation, muscle metabolite contents, and muscle deoxygenation in older adults [n = 6; 70 [+ or -] 5 (67-74) yr] during moderate-intensity exercise ([Mod.sub.1]) and during moderate-intensity exercise preceded by heavy-intensity warm-up exercise ([Mod.sub.2]). The phase 2 V[O.sub.2p] time constant ([tau]V[O.sub.2p]) was reduced (P < 0.05) in [Mod.sub.2] (29 [+ of -] 5 s) compared with [Mod.sub.1] (39 [+ or -] 14 s). PDH activity was elevated (P < 0.05) at baseline prior to [Mod.sub.2] (2.1 [+ or -] 0.6 vs. 1.2 [+ or -] 0.3 mmol acetyl-CoA x [min-kg wet wt-l), and the delay in attaining end exercise activity was abolished. Phosphocreatine breakdown during exercise was reduced (P < 0.05) at both 30 s and 6 min in Mod2 compared with Modl. Near-infrared spectroscopyderived indices of muscle oxygenation were elevated both prior to and throughout Mod2, while muscle deoxygenation kinetics were not different between exercise bouts consistent with elevated perfusion and 02 availability. These results suggest that in older adults, faster Vo2p kinetics following prior heavy-intensity exercise are likely a result of prior activation of mitochondrial enzyme activity in combination with elevated muscle perfusion and O2 availability. V[O.sub/2] kinetics; ageing; pyruvate dehydrogenase; phosphocreatine

Published
2009

Catalog

Books, media, physical & digital resources
See catalog results