Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance

摘要: Background Exercise practitioners often take vitamin C supplements because intense muscular contractile activity can result in oxidative stress, as indicated by altered muscle and blood glutathione concentrations increases protein, DNA, lipid peroxidation. There is, however, considerable debate regarding the beneficial health effects of supplementation. Objective This study was designed to effect on training efficiency rats humans. Design The human double-blind randomized. Fourteen men (27-36 y old) were trained for 8 wk. Five supplemented daily with an oral dose 1 g C. In animal study, 24 male Wistar exercised under 2 different protocols 3 6 Twelve treated a (0.24 mg/cm2 body surface area). Results administration significantly (P=0.014) hampered endurance capacity. adverse may from its capacity reduce exercise-induced expression key transcription factors involved mitochondrial biogenesis. These are peroxisome proliferator-activated receptor co-activator 1, nuclear respiratory factor A. Vitamin also prevented cytochrome (a marker content) antioxidant enzymes superoxide dismutase peroxidase. Conclusion supplementation decreases it prevents some cellular adaptations exercise.