Research

Hormonal

Long-term athletic training and the resulting lower lifetime estrogen exposure significantly reduce the risk of breast and reproductive system cancers in women.

Starting athletic training early in life (high school or earlier) and maintaining it through college can significantly lower your lifetime risk of breast and reproductive cancers. This benefit is likely due to lower lifetime estrogen exposure associated with lower body fat levels.

GoodSupportsHIGH confidence
Data from a study of the long-term reproductive health of 2622 former college athletes compared with 2766 non-athletes show that the former college athletes had a significantly lower lifetime occurrence of breast cancer and cancers of the reproductive system...
Rose E. Frisch · Human Reproduction · 1987

Why this rating

Based on a large cohort study (2622 athletes vs 2766 non-athletes) with significant p-values.

Source

Body fat, menarche, fitness and fertility

Rose E. Frisch · Human Reproduction · 1987

DOI 10.1093/oxfordjournals.humrep.a136582

narrative_review · n=5388Cited 376×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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