An Air Force volunteer performs a rescue simulation as part of a study of combat's physical demands.

An Air Force volunteer performs a rescue simulation as part of a study of combat's physical demands.

U.S. AIR FORCE PHOTO/1ST LT. JOSE R. DAVIS

Learn about the science behind U.S. decision to open combat roles to women

The U.S. military will open all combat positions to women, Secretary of Defense Ashton Carter announced today.

The landmark decision overturns a 1994 rule that bars women from numerous combat positions in the armed services. It also comes in the wake of a major effort by Pentagon researchers to understand the implications of putting women in combat positions, and studies aimed at developing new physical standards for admitting recruits.

Earlier this year, Science’s Kelly Servick took a look inside one such study—an exercise physiologist's effort to set new standards for Air Force combat soldiers—and explored how its researchers and participants were navigating the controversial issue.