system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can a hormone like estrogen cause muscular problems like an ACL tear?
gpt
Estrogens do not cause an ACL tear. However, it is true that joints, particularly joints that are under high mechanical stress (like the knee joint), may be more injury prone in the longterm presence of estrogens. Estrogens influence fibroblasts, the cells that form collagen - the main compound of ligaments. This effect of estrogens on collagen synthesis may explain the increased incidence of ligament injuries in female athletes.