How girls get knee injuries

The NY Times explains how Title IX has led to thousands of girls getting seriouns knee injuries:

Title IX, the federal law enacted in 1972 mandating equal opportunity in sports, has helped to shape a couple of generations of girls who believe they are as capable and as tough as any boy. With a mix of resignation and pride, Rich Pierson said to me: "We've raised these girls to be headstrong and independent. ...

By Janelle's and her mother's count, her club team, with 18 players, had suffered eight A.C.L. tears — eight — during her high-school years: Janelle's two, another player's two and four other girls with one each. A high-school teammate one class above Janelle endured chronic ankle problems and, according to a Miami Herald article, six ankle operations — three in each leg — over the course of her four years on the varsity soccer team.

This casualty rate was not due to some random spike in South Florida. It is part of a national trend in the wake of Title IX and the explosion of sports participation among girls and young women. From travel teams up through some of the signature programs in women's college sports, women are suffering injuries that take them off the field for weeks or seasons at a time, or sometimes forever.

Girls and boys diverge in their physical abilities as they enter puberty and move through adolescence. Higher levels of testosterone allow boys to add muscle and, even without much effort on their part, get stronger. In turn, they become less flexible. Girls, as their estrogen levels increase, tend to add fat rather than muscle. They must train rigorously to get significantly stronger. The influence of estrogen makes girls' ligaments lax, and they outperform boys in tests of overall body flexibility — a performance advantage in many sports, but also an injury risk when not accompanied by sufficient muscle to keep joints in stable, safe positions. Girls tend to run differently than boys — in a less-flexed, more-upright posture — which may put them at greater risk when changing directions and landing from jumps. Because of their wider hips, they are more likely to be knock-kneed — yet another suspected risk factor.

This divergence between the sexes occurs just at the moment when we increasingly ask more of young athletes, especially if they show talent: play longer, play harder, play faster, play for higher stakes. And we ask this of boys and girls equally — unmindful of physical differences.

Phyllis Schlafly warned about this five years ago.