Table 4

Lifetimea physical activityb and breast cancer risk, by intensity of activity

Premenopausal womenPostmenopausal women
Hours/weekCases n = 403Controls n = 483ORc (95% CI)ORd (95% CI)Hours/weekCases n = 847Controls n = 1065ORc (95% CI)ORe (95% CI)
Total activity (MET-hours per week)Total activity (MET-hours per week)
 <451711611.01.0  <453323541.01.0
 45–991241600.740.54–1.020.81 0.58–1.14 45–1022683550.810.65–1.010.850.68–1.07
 ≥1001081620.640.46–0.890.78 0.55–1.10 ≥1032413560.770.62–0.960.820.65–1.03
Total moderatef activityTotal moderatef activity
 <6.81621611.01.0g <7.63433541.01.0g
 6.9–16.61511600.940.69–1.291.05 0.75–1.47 7.6–17.72713560.790.64–0.980.850.68–1.06
 ≥16.7901620.560.40–0.780.67 0.46–0.96 ≥17.82333550.700.56–0.880.740.59–0.94
Total vigoroush activityTotal vigoroush activity
 <6.83434031.01.0i <7.67589401.01.0i
 6.9–16.647491.130.74–1.731.07 0.68–1.68 7.6–17.765721.020.72–1.431.130.79–1.60
 ≥16.713310.500.26–0.970.68 0.34–1.37 ≥17.824430.720.43–1.210.870.51–1.48
  • a From menarche to reference year.

  • b Includes recreational activity, walking, bicycling, strenuous household and outdoor chores, and nonsedentary jobs.

  • c Adjusted for age and race/ethnicity.

  • d Adjusted for age, race/ethnicity, country of birth, education, family history of breast cancer, prior biopsy for benign breast disease, age at menarche, parity, age at first full-term pregnancy, breast-feeding, and BMI.

  • e Adjusted for age, race/ethnicity, country of birth, education, family history of breast cancer, age at menarche, parity, breast-feeding, and age at menopause.

  • f Moderate activities 3–5.9 METS.

  • g Adjusted for above variables and total vigorous activity.

  • h Vigorous activities ≥6 METS.

  • i Adjusted for above variables and total moderate activity.