title: Antioxidants do not prevent postexercise peroxidation and may delay muscle recovery.
abstract: OBJECTIVE
  This study aimed to determine the effects of 4 wk of antioxidants (AOX) supplementation on exercise-induced lipid peroxidation, muscle damage, and inflammation in kayakers.
  
  
  METHODS
  Subjects (n = 20) were randomly assigned to receive a placebo (PLA) or an AOX capsule (AOX; 272 mg of alpha-tocopherol, 400 mg of vitamin C, 30 mg of beta-carotene, 2 mg of lutein, 400 mug of selenium, 30 mg of zinc, and 600 mg of magnesium). Blood samples were collected at rest and 15 min after a 1000-m kayak race, both before and after the supplementation period, for analysis of alpha-tocopherol, alpha-carotene, beta-carotene, lycopene, lutein plus zeaxanthin, vitamin C, uric acid, total AOX status (TAS), thiobarbituric reactive acid substances (TBARS) and interleukin-6 (IL-6) levels, and creatine kinase (CK), superoxide dismutase (SOD), glutathione reductase (Gr), and glutathione peroxidase (GPx) activities.
  
  
  RESULTS
  With supplementation, plasma alpha-tocopherol (P = 0.003) and beta-carotene (P = 0.007) augmented significantly in the AOX group. IL-6 (exercise, P = 0.039), TBARS (exercise, P < 0.001), and uric acid (exercise, P = 0.032) increased significantly in response to the exercise regardless of treatment group. Cortisol level raised more from pre- to postsupplementation period in the PLA group (time x supplementation, P = 0.002). Although TAS declined after exercise before intervention, it increased above preexercise values after the 4-wk period in the AOX group (supplementation x time x exercise, P = 0.034). CK increased after exercise in both groups (exercise effect, P < 0.001) and decreased from week 0 to week 4 more markedly in the PLA group (supplementation x time, P = 0.049).
  
  
  CONCLUSIONS
  AOX supplementation does not offer protection against exercise-induced lipid peroxidation and inflammation and may hinder the recovery of muscle damage.
authors: Faculty of Nutrition and Food Sciences, University of Porto, Porto, Potugal. vhugoteixeira@fcna.up.pt
authors: Vitor H
authors: VH
authors: Teixeira
authors: Hugo F
authors: HF
authors: Valente
authors: Susana I
authors: SI
authors: Casal
authors: A Franklim
authors: AF
authors: Marques
authors: Pedro A
authors: PA
authors: Moreira
mesh_terms: D000293:Adolescent; D000975:Antioxidants / Q000008:administration & dosage / Q000378:metabolism*; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000293:injuries; D018384:Oxidative Stress / Q000187:drug effects; D011174:Portugal; D055815:Young Adult
chemical_list: D000975:Antioxidants