Girls are as athletic as boys, a recent study says — if you take the terms quite literally and limit yourself to self-selected swimmers:
Researchers from Indiana University analyzed data from more than 1.9 million swim meets, registered with the organizaton USA Swimming. The meets they studied, all 50-yard freestyle events, included both boys and girls between the ages of six and 19, broken up into age groups. They found no gender difference in the performance of six to eight-year-olds and a negligible difference between 11 and 12-year-old boys and girls. Around puberty — ages 13 to 16 — the accelerated growth and muscle development of many boys meant they began to surpass the performance of female counterparts.