To be sure, a small number of women can compete physically with some men. But privacy issues do not disappear just because a woman can do pull-ups. Among the services that use gender-integrated basic training, the Air Force has done no comparative studies and the Army and Navy have conducted extremely limited comparative studies with mixed results. If that is true, then there is no reason why the services should expend the extra effort and expense for gender-integrated training. And yet, common sense makes me question whether it is true that there are no differences in training outcomes.
Data show that women recruits suffer higher injury rates than men in basic training in all services.
On average, women perform well below men in terms of strength, endurance, and aerobic capacity. Physical training that is sufficiently intense for men to achieve or maintain fitness is likely to be excessively intense for most women. Studies of gender-integrated training have focused primarily on issues of sociological and psychological, but not necessarily military, interest. More recent biological studies, however, definitively link aggression and testosterone. The trainers I spoke with described their very long workdays and the complications of training male and female recruits together.