By Eliza Gray
September 10, 2015

All-male ground combat troops outperformed units that included both men and women, according to new data released on Thursday, complicating the discussion about the upcoming integration of women into more roles in the military.

During an experiment conducted by the Marine Corps, all male teams outperformed mixed gender squads on 69% of the tasks. All-male squads were faster than the gender-integreated squads, particularly when carrying heavier loads, and they also had better marksmanship.

The research also found that women were six times more likely to be injured than their male counterparts, and nearly 27% of female injuries were caused by moving with a heavy load, compared to only 13% for men.

According to the Marine Corps Times, the study was conducted over the course of nine months with about 400 marine volunteers, a quarter of whom were women. One limitation of the study was that many of the men generally benefited from more experience, having previously served in combat troops, while the women came directly from school or non-combat assignments.

The data could influence the roles available in the armed services for women, who have become gradually more integrated into the military. In August, two women made history by being the first to graduate from Army Ranger School. The Marine Corps study was conducted in preparation for a looming deadline of Jan. 1, 2016 for military service chiefs to integrate women into combat units, or submit a waiver request for certain units.

“The true basis of this was to gather some hard qualitative metrics on what we would expect to see in combat effectiveness,” said Paul Johnson, the principal investigator for the integration experiment, in a briefing. “Is every member of the group contributing equally to the outcome? That’s important to know.”

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