Effects of Eccentric and Concentric Cycling Exercise Regimens on Hypoxia‐Mediated Mitochondrial Bioenergetics of Platelets in Sedentary Males

Abstract

Rehabilitation Science, Medical College, Chang Gung University, Taoyuan City, Taiwan Physical exercise influences platelet function according to responses dependent on the type and intensity of exercise. Mitochondrial bioenergetics is a critical role in the platelets function. The purpose of this study was to investigate the effects of eccentric (ECE) and concentric (CCE) cycling exercise regimens on mitochondrial oxidative phosphorylation of platelets during hypoxic stress. Twenty‐two healthy sedentary men were randomized to either ECE (n=11) or CCE (n=11) group. These subjects progressively performed ECE or CCE at 45% to 70% VO2max on a bicycle ergometer for 40 min/day, 5 days/week for 6 weeks. Mitochondrial oxidative phosphorylation were measured by a high resolution respirometer (Oxygraph‐2k) at rest and after hypoxia exercise test (HE, 100W under 12% O2 for 40 min). The result demonstrated that both ECE and CCE regimens increased complex I‐linked O2 consumption rate (OCR), complex‐II linked OCR, fatty acid oxidation (FAO)‐linked OCR and GpDH‐linked OCR. Besides, ECE significantly diminished the suppressions of complex II‐ and GpDH‐linked respirations during HE. Hence, either ECE or CCE effectively enhances efficacy of mitochondrial oxidative phosphorylation in platelets. Moreover, ECE has more superior to alleviate the extent of mitochondrial dysfunction evoked by hypoxia stress.