Research

Hormonal

Engaging in moderate physical activity, specifically brisk walking for approximately 5 hours per week (27 MET-h/wk), significantly reduces the risk of invasive breast cancer in postmenopausal women.

If you are postmenopausal, aim for about one hour of brisk walking every day. You do not need to do high-intensity interval training or heavy lifting to lower your breast cancer risk. Consistency with moderate activity like brisk walking is the key factor identified in this study. If you were previously inactive, starting this routine now can still provide a protective benefit.

GoodSupportsHIGH confidence
Compared with less than 3 MET-h/wk... women engaged in higher amounts of recent total physical activity were at lower breast cancer risk (>=27 MET-h/wk [approximately 1 h/d of brisk walking]: HR, 0.85; 95% CI, 0.78-0.93; P<.001 for trend).
A. Heather Eliassen et al. · Archives of Internal Medicine · 2010

Why this rating

Large prospective cohort (Nurses' Health Study), long follow-up (20 years), and rigorous statistical adjustment for confounders, though observational design prevents causal proof.

Source

Physical Activity and Risk of Breast Cancer Among Postmenopausal Women

A. Heather Eliassen et al. · Archives of Internal Medicine · 2010

DOI 10.1001/archinternmed.2010.363

cohort · n=95396Cited 188×
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DOI resolved against Crossref · corpus check 2026-06-10

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