Micronutrients & recovery
Supplementation with high-dose Vitamin E and/or Vitamin C blunts skeletal muscle adaptations to endurance and resistance training, including mitochondrial biogenesis and hypertrophy signaling pathways, without improving performance metrics like VO2max.
If you are training to improve fitness or build muscle, avoid high-dose Vitamin C and E supplements. They block the cellular signals your body needs to adapt to exercise. Instead, get your antioxidants from whole foods like fruits and vegetables, which support health without interfering with your training progress.
Current evidence suggests that antioxidant supplementation may impair these adaptations. ... it appears to be unlikely that free radical production via exercise will negatively impact performance in the long term ... there is convincing evidence that vitamin C and E, taken alone or in combination blunts some skeletal muscle adaptations to endurance training.
Why this rating
Based on a systematic review of multiple human studies showing consistent blunting of molecular adaptations, though performance outcomes remain neutral.
Source
Antioxidants and Exercise Performance: With a Focus on Vitamin E and C Supplementation
Madalyn Higgins et al. · International Journal of Environmental Research and Public Health · 2020
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