Fast-twitch muscle fibers hypertrophy is hampered by antioxidant supplementation during atrophy rehabilitation in rats

The role of antioxidant supplementation on muscle recovery after disuse is unknown. The aim was to investigate the effect of Vitamin C and E supplementation on muscle recovery after hindlimb suspension. Twenty-two Wistar rats were allocated into 4 groups: exercise with supplementation (VIT, [Formula: see text]); exercise with placebo (PLA, [Formula: see text]); hindlimb suspension (SUSP, [Formula: see text]), and control (CON, [Formula: see text]). All groups, except for CON, were submitted to a hindlimb suspension protocol for 10 days. Then, VIT and PLA underwent 10 days of a rehabilitation protocol consisting of exercise on a treadmill. VIT received vitamin C (250 mg/kg/day) and E (360 mg/kg) during rehabilitation. Samples of soleus and tibialis anterior were prepared for cross-sectional area (CSA) and biochemical analysis. Both VIT (1265.6[Formula: see text]m[Formula: see text]2, 95% CI: 1234.6–1290.3) and PLA (1280.9[Formula: see text]m[Formula: see text]2, 95% CI: 1296.4–1354.9) presented higher CSA of the soleus in relation to CON (816.66[Formula: see text]m[Formula: see text]2, 95% CI: 866.3–904.0, [Formula: see text] [Formula: see text] 0.05) with no difference between them. Both VIT (1276.9[Formula: see text]m[Formula: see text]2, 95% CI: 1378.7–1484.6) and PLA (1573.3[Formula: see text]m[Formula: see text]2, 95% CI: 1553.9–1651.5) presented higher tibialis anterior CSA in relation to CON (1041.56[Formula: see text]m[Formula: see text]2, 95% CI: 1119.1–1185.2, [Formula: see text] [Formula: see text] 0.05). In this muscle, CSA of PLA was higher than VIT ([Formula: see text] [Formula: see text] 0.05). Vitamin’s supplementation attenuated tibialis anterior hypertrophy following the rehabilitation protocol.