The effects of an antioxidant-supplemented beverage on exercise-induced oxidative stress: results from a placebo-controlled double-blind study in cyclists

Eur J Appl Physiol. 2005 Dec;95(5-6):543-9. doi: 10.1007/s00421-005-0017-4. Epub 2005 Aug 31.


The objective of this study was to test the effects of an antioxidant-supplemented beverage on exercise-induced oxidative stress in moderately trained cyclists. A double-blind study was conducted in moderately trained cyclists. They were randomly allocated to receive either an antioxidant (13 subjects) or a placebo (13 subjects) 15 min pre-exercise (30 and during a 90 min constant-load test (30 min(-1)) on a bicycle ergometer at 70% VO2max The supplemented beverage contained black grape (81 g/l), raspberry (93 g/l) and red currant (39 g/l) concentrates, and its total antioxidant capacity, measured by the ABTS(.+) technique, was 0.41 mM Trolox. No significant difference from basal to post-exercise period was detected for plasma TBARS in either the placebo group or the group receiving the antioxidant supplemented beverage. Post-exercise carbonyls decreased by 29% in the group receiving antioxidants, and the pattern of change was significantly different between antioxidant and placebo conditions. The urinary excretion of 8-OHdG increased significantly by 21% in the placebo group. Again differences in the pre- to post-exercise change were significant between both conditions These results suggest that in moderately trained cyclists, antioxidant supplementation counters oxidative stress induced by a 90 min exercise at 70% VO2max.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Adult
  • Antioxidants / administration & dosage*
  • Beverages*
  • Creatine Kinase / blood
  • Deoxyguanosine / analogs & derivatives
  • Deoxyguanosine / urine
  • Double-Blind Method
  • Exercise / physiology*
  • Fruit
  • Humans
  • Male
  • Oxidative Stress / physiology*
  • Protein Carbonylation / physiology
  • Thiobarbituric Acid Reactive Substances / metabolism


  • Antioxidants
  • Thiobarbituric Acid Reactive Substances
  • 8-Hydroxy-2'-Deoxyguanosine
  • Creatine Kinase
  • Deoxyguanosine