Men also have more red blood cells than women, and their hearts and lungs are bigger too. Some of these advantages are irreversible, Briner said, even if testosterone levels are cut. “Insofar as there is an ‘athleticism gene,’” it’s the gene on the Y chromosome that signals the development of testes and the production of testosterone, writes David Epstein in his book, “The Sports Gene.”
These differences give men a distinct advantage over women, and they’re the reason that sport is segregated by gender. Which is all fine and great until it comes time to sort women from men....
June 29, 2016
"People who go through male puberty are taller, have bigger bones and develop greater muscle mass than those who go through female puberty..."
"... said William Briner, a sports medicine physician at the Hospital for Special Surgery in Uniondale, New York, during a session on transgender athletes at the American College of Sports Medicine meeting in early June."