title: Recent physical activity in relation to DNA damage and repair using the comet assay.
abstract: BACKGROUND
  Limited evidence suggests that very high-intensity exercise is positively associated with DNA damage but moderate exercise may be associated with DNA repair.
  
  
  METHODS
  Participants were 220 healthy, Washington State 50- to 76-year-olds in the validity/biomarker substudy of the VITamins And Lifestyle (VITAL) cohort, who provided blood samples and completed questionnaires assessing recent physical activity and demographic and health factors. Measures included nested activity subsets: total activity, moderate- plus high-intensity activity, and high-intensity activity. DNA damage (n = 122) and repair (n = 99) were measured using the comet assay. Multivariate linear regression was used to estimate regression coefficients and associated 95% confidence intervals (CIs) for relationships between MET-hours per week of activity and each DNA outcome (damage, and 15- and 60-minute repair capacities).
  
  
  RESULTS
  DNA damage was not associated with any measure of activity. However, 60-minute DNA repair was positively associated with both total activity (β = 0.21, 95% CI: 0.0057-0.412; P = .044) and high-intensity activity (β = 0.31, 95% CI: 0.20-0.60; P = .036), adjusting for age, sex, BMI, and current multivitamin use.
  
  
  CONCLUSIONS
  This study is the first to assess broad ranges of activity intensity levels related to DNA damage and repair. Physical activity was unrelated to DNA damage but was associated with increased repair.
authors: Dept of Epidemiology, University of Washington, Seattle, WA.
authors: Stephanie Whisnant
authors: SW
authors: Cash
authors: Shirley A
authors: SA
authors: Beresford
authors: Thomas L
authors: TL
authors: Vaughan
authors: Patrick J
authors: PJ
authors: Heagerty
authors: Leslie
authors: L
authors: Bernstein
authors: Emily
authors: E
authors: White
authors: Marian L
authors: ML
authors: Neuhouser
mesh_terms: D000368:Aged; D015992:Body Mass Index; D020552:Comet Assay; D004249:DNA Damage / Q000502:physiology*; D004260:DNA Repair / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000209:etiology / Q000517:prevention & control*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D014861:Washington