Vitamin C and E supplements may weaken improvements in muscle endurance by interfering with cellular adaptations in exercised muscles, suggests a new study published in The Journal of Physiology. Experts explain that vitamin C and E supplements block the training-induced increase of mitochondrial proteins, which are necessary for enhancing muscle endurance. In an 11-week trial led by subject specialists, 54 healthy young men and women were randomly assigned to receive either 1,000 mg of vitamin C and 235 mg of vitamin E (in line with the amounts found in store supplements), or a placebo (a pill that contains no active ingredients). Neither the individuals nor the researchers knew whether the participants received the vitamins or the placebos. The participants completed a resistance training program, consisting of three to four sessions per week, primarily of currents. Fitness tests, blood samples, and muscle biopsies were taken before and after the intervention. While the supplements did not affect maximum oxygen consumption or the results of a 20-meter test, the results showed that markers for the production of new muscle mitochondria - the energy supply for cells - only increased in the non-supplement group. Experts highlighted: "Our results indicate that high doses of vitamin C and E - which are commonly found in supplements - should be used with caution, especially if you are undertaking resistance training." Further studies are needed to determine the underlying mechanisms of these results, but experts speculate that the vitamins interfered with cellular signaling and the expression of certain genes. Previous studies show that exercise increases the production of muscular oxidants, which are involved in signaling processes that lead to muscle adaptation. It is possible that high doses of vitamins C and E act as antioxidants and remove some of this oxidative stress, thereby blocking the development of muscle endurance. We recommend: Healthy Snacks