Research

Hormonal

Breast cancer survivors who engage in moderate-to-vigorous physical activity (≥9 MET-hours/week) experience a significantly reduced risk of breast cancer recurrence and all-cause mortality compared to inactive survivors.

Aim for at least 9 MET-hours of moderate-to-vigorous activity per week, which translates to roughly 3 hours of brisk walking. This level of activity is strongly associated with a 50% reduction in breast cancer-specific mortality and recurrence risk. If you were inactive before diagnosis, increasing your activity to this level post-diagnosis offers the greatest survival benefit.

ModerateSupportsMEDIUM confidence
The landmark study is the Nurses’ Health Study... After adjusting for factors predictive of survival after breast cancer, compared with women who engaged in less than 3 MET-hours/week of physical activity, the relative risk (RR) of death from breast cancer was... 0.50 (95% CI, 0.31–0.82) for 9 to 14.9 MET-hours/week... the RR of breast cancer recurrence was... 0.57 (95% CI, 0.38–0.85) 9 to 14.9 MET-hours/week.
Mark J. Haykowsky et al. · American Society of Clinical Oncology Educational Book · 2017

Why this rating

Evidence is primarily from observational cohort studies (Nurses' Health Study, LACE, WHI) which are subject to self-reporting bias, though consistent across multiple large cohorts.

Source

Lifestyle Interventions to Improve Cardiorespiratory Fitness and Reduce Breast Cancer Recurrence

Mark J. Haykowsky et al. · American Society of Clinical Oncology Educational Book · 2017

DOI 10.1200/edbk_175349

narrative_reviewCited 21×
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DOI resolved against Crossref · corpus check 2026-06-10

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