Table 2.

Vigorous exercise at baseline in relation to incidence of breast cancer overall and ER+ and ER breast cancer

All breast cancerER+ breast cancerER breast cancer
h/wkCasesPerson-yearsIRRa (95% CI)CasesIRR (95% CI)CasesIRR (95% CI)
<1773313,9001.00 (Ref.)3821.00 (Ref.)2281.00 (Ref.)
111762,9390.85 (0.70–1.03)590.86 (0.66–1.14)350.83 (0.58–1.18)
214967,0810.99 (0.83–1.19)761.00 (0.78–1.29)451.00 (0.72–1.38)
3–415977,2430.94 (0.79–1.12)840.98 (0.77–1.25)450.88 (0.63–1.22)
5–66935,7930.89 (0.69–1.14)360.92 (0.65–1.30)230.97 (0.63–1.50)
≥76339,5930.74 (0.57–0.96)320.75 (0.52–1.09)220.85 (0.55–1.33)
Ptrend = 0.05Ptrend = 0.28Ptrend = 0.43
  • aIRRs adjusted for age (single year), time period (questionnaire cycle), years of education (≤12, 13–15, 16, ≥17), parity (0, 1, 2, ≥3), vegetable/fruit dietary pattern (quintiles), and meat/fried foods dietary pattern (quintiles)