Interesting and well-controlled study to understand whether antioxidant megadoses blunt training adaptations or not.
A lot of contradictory evidence is present on the topic. As seen in this study, however, cell signalling is compromised when high doses of vitamin C and E are ingested on a daily basis.
👫54 recreationally endurance-trained men and women participated in a double-blind randomised controlled trial. Matched for VO2max and anthropometrics.
⚖️They completed an endurance training program of the duration of 11 weeks, with three to four sessions/week.
💊Control participants received 2 pills of 500mg of vitamin C and 117mg of vitamin E. Two pills were consumed 1-3hr before training and two pills within 1hr after training.
🔬VO2max improved to the same degree in both groups, as well as running performance in 20m shuttle test.
Cell signalling was compromised in the control group in regards to mitochondrial COX4 protein content, PGC1a (cytosolic protein level), CDC42 and MAPK1 mRNA.
🧬 Supplementing right before and after training sessions could have further enhanced the blunting effect of mitochondrial biogenesis, as in other studies this was not seen despite the same dosing.