TY - JOUR

T1 - Antioxidant supplementation does not alter endurance training adaptation

AU - Yfanti, Christina

AU - Åkerström, Thorbjörn

AU - Nielsen, Søren

AU - Nielsen, Anders R.

AU - Mounier, Remi

AU - Mortensen, Ole H.

AU - Lykkesfeldt, Jens

AU - Rose, Adam John

AU - Fischer, Christian P

AU - Pedersen, Bente Klarlund

N1 - CURIS 2010 5200 036

PY - 2010/7/1

Y1 - 2010/7/1

N2 - BACKGROUND: There is a considerable commercial market, especially within the sports community, claiming the need for antioxidant supplementation. One argument for antioxidant supplementation in sports is that physical exercise is associated with increased reactive oxygen and nitrogen species (RONS) production, which may cause cell damage. However, RONS production may also activate redox sensitive signaling pathways and transcription factors, which subsequently may promote training adaptation. PURPOSE: Our aim was to investigate the effects of combined vitamin C and E supplementation to healthy individuals on different measures of exercise performance after endurance training. METHODS:: Using a double-blinded placebo-controlled design, moderately trained young men received either oral supplementation with vitamins C and E (n=11) or placebo (n=10) before and during 12 weeks of supervised, strenuous bicycle exercise training of a frequency of 5 days/week. Muscle biopsies were obtained before and after training. RESULTS:: After the training period, maximal oxygen consumption, maximal power output, and workload at lactate threshold all increased markedly (P < .01) in both groups. Also, glycogen concentration, citrate synthase (CS), and beta-hydroxyacyl-CoA dehydrogenase (beta-HAD) activity in muscle were significantly higher in response to training (P < .01) in both groups. However, there were no differences between the two groups with regard to any of the physiological and metabolic variables measured. CONCLUSION: Our results suggest that administration of vitamins C and E to individuals with no prior vitamin deficiencies has no effect on physical adaptations to strenuous endurance training.

AB - BACKGROUND: There is a considerable commercial market, especially within the sports community, claiming the need for antioxidant supplementation. One argument for antioxidant supplementation in sports is that physical exercise is associated with increased reactive oxygen and nitrogen species (RONS) production, which may cause cell damage. However, RONS production may also activate redox sensitive signaling pathways and transcription factors, which subsequently may promote training adaptation. PURPOSE: Our aim was to investigate the effects of combined vitamin C and E supplementation to healthy individuals on different measures of exercise performance after endurance training. METHODS:: Using a double-blinded placebo-controlled design, moderately trained young men received either oral supplementation with vitamins C and E (n=11) or placebo (n=10) before and during 12 weeks of supervised, strenuous bicycle exercise training of a frequency of 5 days/week. Muscle biopsies were obtained before and after training. RESULTS:: After the training period, maximal oxygen consumption, maximal power output, and workload at lactate threshold all increased markedly (P < .01) in both groups. Also, glycogen concentration, citrate synthase (CS), and beta-hydroxyacyl-CoA dehydrogenase (beta-HAD) activity in muscle were significantly higher in response to training (P < .01) in both groups. However, there were no differences between the two groups with regard to any of the physiological and metabolic variables measured. CONCLUSION: Our results suggest that administration of vitamins C and E to individuals with no prior vitamin deficiencies has no effect on physical adaptations to strenuous endurance training.

U2 - 10.1249/MSS.0b013e3181cd76be

DO - 10.1249/MSS.0b013e3181cd76be

M3 - Journal article

VL - 42

SP - 1388

EP - 1395

JO - Medicine and Science in Sports and Exercise

JF - Medicine and Science in Sports and Exercise

SN - 0195-9131

IS - 7

ER -