Effect of strength training and antioxidant supplementation on perceived and performance fatigability of breast cancer survivors - A randomized, double-blinded, placebo-controlled study.

This randomized, double-blinded, placebo-controlled study aimed to investigate the effect of strength training (ST) combined with vitamin C and E supplementation on perceived and performance fatigability in breast cancer survivors (BCS). Twenty-five BCS were randomly assigned to one of two groups: vitamins (VIT; n = 12; 51.0 +/- 9.0 years); or placebo (PLA; n = 13; 48.2 +/- 8.3 years). Both groups performed a 10-week ST protocol, twice a week. VIT was supplemented with vitamins C (500mg/day) and E (180mg/day) and PLA with polydextrose (1g/day), once a day after breakfast. At the beginning and at the end of training period, perceived fatigability was assessed using MFI-20 (general fatigue and physical fatigue). Performance fatigability was assessed during 30 maximal isokinetic knee extension at 120 masculine/s-1. General fatigue reduced similarly in VIT (p = 0.004) and PLA (p = 0.011). Physical fatigue reduced similarly in both, VIT (p = 0.011) and PLA (p = 0.001). Performance fatigability also decreased similarly in VIT (p = 0.026) and PLA (p 0.05). In summary, antioxidants supplementation does not add any positive synergistic effect to ST on improving perceived or performance fatigability in BCS. Novelty: -Strength training with maximal repetitions reduces perceived and performance fatigability of BCS. -Vitamins C and E supplementation does no add any positive synergistic effect to ST on reducing fatigability in BCS.