title: Long-term and baseline recreational physical activity and risk of endometrial cancer: the California Teachers Study.
abstract: BACKGROUND
  Physical activity may be associated with decreasing endometrial cancer risk; it remains unclear whether the association is modified by body size.
  
  
  METHODS
  Among 93 888 eligible California Teachers Study participants, 976 were diagnosed with incident endometrial cancer between 1995-1996 and 2007. Cox proportional hazards regression methods were used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for endometrial cancer associated with long-term (high school through age 54 years) and baseline (3 years prior to joining the cohort) strenuous and moderate recreational physical activity, overall and by body size.
  
  
  RESULTS
  Increased baseline strenuous recreational physical activity was associated with decreased endometrial cancer risk (Ptrend=0.006) with approximately 25% lower risk among women exercising >3 h per week per year than among those exercising <1/2 h per week per year (RR, 0.76; 95% CI, 0.63-0.92). This inverse association was observed among overweight/obese women (body mass index ≥25 kg m(-2); Ptrend=0.006), but not among thinner women (Ptrend=0.12). Baseline moderate activity was associated with lower risk among overweight/obese women.
  
  
  CONCLUSIONS
  Increasing physical activity, particularly strenuous activity, may be a lifestyle change that overweight and obese women can implement to reduce their endometrial cancer risk.
authors.affiliation: Department of Population Sciences, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA. cdieli@usc.edu
authors.forename: C M
authors.initials: CM
authors.lastname: Dieli-Conwright
authors.forename: H
authors.initials: H
authors.lastname: Ma
authors.forename: J V
authors.initials: JV
authors.lastname: Lacey
authors.forename: K D
authors.initials: KD
authors.lastname: Henderson
authors.forename: S
authors.initials: S
authors.lastname: Neuhausen
authors.forename: P L
authors.initials: PL
authors.lastname: Horn-Ross
authors.forename: D
authors.initials: D
authors.lastname: Deapen
authors.forename: J
authors.initials: J
authors.lastname: Sullivan-Halley
authors.forename: L
authors.initials: L
authors.lastname: Bernstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002140:California / Q000453:epidemiology; D016889:Endometrial Neoplasms / Q000453:epidemiology*; D005178:Faculty / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008875:Middle Aged; D009043:Motor Activity; D016016:Proportional Hazards Models; D011998:Recreation; D012307:Risk Factors; D055815:Young Adult