U.S. Army Pfc. Amy Alexanders dresses in her Marne Standard battle gear before taking part in a physical demands study, Feb. 25, 2014, in Ft. Stewart, Ga.

FORT STEWART, Ga. - Army researchers are studying how hard soldiers - both women and men - have to work at battlefield tasks as the scientists strive to define gender-neutral fitness standards for troops in combat units.

At Fort Stewart in southeast Georgia, dozens of soldier-volunteers donned oxygen masks and heart-rate monitors Tuesday and performed such drills as carrying heavy cans of ammunition and dashing through obstacle courses. It's part of the Army's plan to open combat jobs to women as early as 2016.

Physical exertion data collected by the Army scientists will be used to develop a physical fitness test that mimics the essential tasks that soldiers must be able to perform on the front lines. The same test will be given to men and women alike.