Research

Hormonal

High estrogen levels during the ovulatory phase of the menstrual cycle decrease ligament stiffness by inhibiting lysyl oxidase activity, leading to increased knee laxity and a significantly higher risk of anterior cruciate ligament (ACL) injury.

Female athletes should be aware that their risk of ACL injury increases during the ovulatory phase of their menstrual cycle due to hormonal changes that loosen ligaments. While you cannot change your hormones, you can adjust training loads or focus on neuromuscular control exercises during this high-risk window to mitigate the increased laxity.

GoodSupportsHIGH confidence
High estrogen levels can decrease power and performance and make women more prone for catastrophic ligament injury... estrogen decreases stiffness, and this directly affects performance and injury rates.
Nkechinyere Chidi-Ogbolu et al. · Frontiers in Physiology · 2019

Why this rating

Supported by multiple human observational studies showing correlation between estrogen peaks and laxity/injury, plus mechanistic cell culture data.

Source

Effect of Estrogen on Musculoskeletal Performance and Injury Risk

Nkechinyere Chidi-Ogbolu et al. · Frontiers in Physiology · 2019

DOI 10.3389/fphys.2018.01834

narrative_reviewCited 358×
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DOI resolved against Crossref · corpus check 2026-06-10

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