Oxidative stress, inflammation and recovery of muscle function after damaging exercise: effect of 6-week mixed antioxidant supplementation

Abstract

There is no consensus regarding the effects of mixed antioxidant vitamin C and/or vitamin E supplementation on oxidative stress responses to exercise and restoration of muscle function. Thirty-eight men were randomly assigned to receive either placebo group (n = 18) or mixed antioxidant (primarily vitamin C & E) supplements (n = 20) in a double-blind manner. After 6 weeks, participants performed 90 min of intermittent shuttle-running. Peak isometric torque of the knee flexors/extensors and range of motion at this joint were determined before and after exercise, with recovery of these variables tracked for up to 168 h post-exercise. Antioxidant supplementation elevated pre-exercise plasma vitamin C (93 ± 8 μmol l(-1)) and vitamin E (11 ± 3 μmol l(-1)) concentrations relative to baseline (P < 0.001) and the placebo group (P ≤ 0.02). Exercise reduced peak isometric torque (i.e. 9-19% relative to baseline; P ≤ 0.001), which persisted for the first 48 h of recovery with no difference between treatment groups. In contrast, changes in the urine concentration of F(2)-isoprostanes responded differently to each treatment (P = 0.04), with a tendency for higher concentrations after 48 h of recovery in the supplemented group (6.2 ± 6.1 vs. 3.7 ± 3.4 ng ml(-1)). Vitamin C & E supplementation also affected serum cortisol concentrations, with an attenuated increase from baseline to the peak values reached after 1 h of recovery compared with the placebo group (P = 0.02) and serum interleukin-6 concentrations were higher after 1 h of recovery in the antioxidant group (11.3 ± 3.4 pg ml(-1)) than the placebo group (6.2 ± 3.8 pg ml(-1); P = 0.05). Combined vitamin C & E supplementation neither reduced markers of oxidative stress or inflammation nor did it facilitate recovery of muscle function after exercise-induced muscle damage.

Effect of fruit and vegetable intake on oxidative stress and inflammation in COPD: a randomised controlled trial

“…Sputum neutrophil elastase was measured using an in-house continuous activity assay [21]. Sputum and urinary 8-isoprostanes were measured using an AutoDELFIA assay (PerkinElmer, Cambridge, UK) [22].…”

No effect of antioxidant supplementation on muscle performance and blood redox status adaptations to eccentric training

“…Indeed, several studies have indicated that antioxidant supplementation induces a positive effect (1, 2), a negative effect (3,4), or no effect (5, 6) on muscle performance. Likewise, several studies have reported that antioxidant supplementation attenuates oxidative stress (7)(8)(9), others have reported that it induces a prooxidant effect (10)(11)(12)(13), and others have reported that it does not affect redox status (5,14,15).…”

Delayed Onset Muscle Soreness and Mechanisms: Relation with Oxidative Stress: Review

“…74,75 Bunun yanı sıra Close ve ark., iki haftalık C vitamini uygulamasının yokuş aşağı koşularda GKA düzeyinden bağımsız olarak oksidatif stres düzeyini azalttığını saptamışlardır. 76 Thompson ve ark., yokuş aşağı koşu sırasında oluşan kas hasarı biyo-işaretlerinin uzun süre C vitamini kullanan grupta ve plasebo grubunda benzer olduğunu, aynı zamanda C vitamini kullanımının IL-6 oluşumuna etkisi olmadığını belirlemişlerdir.…”