The Army is in the midst of a top-to-bottom study of the physical and mental strength required to perform each military occupational specialty (MOS). After the three-year study, Army leaders hope to have enough data to determine what it takes to perform combat-related jobs in infantry, armor, artillery, and combat engineering. A team that includes exercise physiologists, biomechanists, psychologists, a physician assistant and an occupational therapist from U.S. Army Training and Doctrine Command (TRADOC) and the Natick, Mass.-based U.S. Army Research Institute of Environmental Medicine will measure volunteer soldiers’ heart and breathing rates and oxygen consumption.