title: Physical activity and risk of colon adenoma: a meta-analysis.
abstract: BACKGROUND
  Little evidence is available on the relation of physical activity with colon adenomas, a colon cancer precursor.
  
  
  METHODS
  We conducted a systematic literature review and meta-analysis of published studies (in English) through April 2010, examining physical activity or exercise and risk or prevalence of colon adenoma or polyp. Random effects models were used to estimate relative risks (RRs) and corresponding confidence intervals (CIs). A total of 20 studies were identified that examined the association and provided RRs and corresponding 95% CIs.
  
  
  RESULTS
  A significant inverse association between physical activity and colon adenomas was found with an overall RR of 0.84 (CI: 0.77-0.92). The association was similar in men (RR=0.81, CI: 0.67-0.98) and women (RR=0.87, CI: 0.74-1.02). The association appeared slightly stronger in large/advanced polyps (RR=0.70, CI: 0.56-0.88).
  
  
  CONCLUSIONS
  This study confirms previous reports of a significant inverse association of physical activity and colon adenoma, and suggests that physical activity can have an important role in colon cancer prevention.
authors.affiliation: Division of Public Health Sciences, Department of Surgery, Washington University School of Medicine in St Louis and Alvin J Siteman Cancer Center, 660 S Euclid Avenue, Box 8100, St Louis, MO 63110, USA. wolink@wustl.edu
authors.forename: K Y
authors.initials: KY
authors.lastname: Wolin
authors.forename: Y
authors.initials: Y
authors.lastname: Yan
authors.forename: G A
authors.initials: GA
authors.lastname: Colditz
mesh_terms: D000236:Adenoma / Q000453:epidemiology*; D003110:Colonic Neoplasms / Q000453:epidemiology*; D003111:Colonic Polyps / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity; D012306:Risk