RESUMO
Sternuous physical exercise may lower endogenous antioxidant bioactivity as a result of excessive generation of reactive oxygen species [ROS] and overproduction of lactic acid. Excessive ROS production can lead to intensive peroxidation of cell membrane lipids in erythrocytes and muscle cells. Exercise-induced oxidative stress and excessive lactic acid production can therefore accelerate muscle fatigability and exhaustion during physical activity. The aim of this study was to evaluate the effect of maximal physical exercise on plasma malondialdehyde [MBA], and lactate levels in both untreated and coenzyme Q10 [CoQ10]-pretreated Karate sportsmen as compared to individuals with normal physical activity. The effect of CoQ10 -pretreatment on physical endurance and fittness was also studied. Mean plasma MBA and lactate concentrations were significantly lower in Karate sportsmen than in individuals with normal physical activity [control group] immediately after extreme physical exercise. Also, mean plasma MDA and lactate concentrations were significantly lower in CoQ10-pretreated sportsmen than in untreated sportsmen following exhaustive physical exercise. Besides, CoQ10-pretreated Karate sportsmen showed significant increase in exercise tolerance [endurance] compared to untreated sportsmen. We conclude that CoQ10 may improve physical endurance and fittness and reduce muscle fatigue in athletes probably through augmenting endogenous antioxidanmt defenses