New research suggests that the nearly 600% increase in girls' sports participation following the passage of Title IX has contributed to health benefits for women. In the current issue of Evaluation Review, Robert Kaestner and Xin Xu report that "adult women who were affected by Title IX and had greater opportunity to participate in athletics while young had lower body mass index (BMI) and lower rates of obesity and reported being more physically active than women who were not afforded these opportunities." (The researchers also note that while the results were statistically significant, the was small, which I'm told means that there's a modest trend toward improvement, rather than a major change.)
Citation: Robert Kaestner & Xin Xu, Title IX, Girls Sports, and Adult Female Activity and Weight, 34 Evaluation Rev. 52 (2010).