Update: Exertional rhabdomyolysis, active component, U.S. Armed Forces 2008-2012.

In 2012, there were 402 incident episodes of rhabdomyolysis likely due to physical exertion and/or heat stress ("exertional rhabdomyolysis") among U.S. service members. The annual rates of exertional rhabdomyolysis increased 30 percent from 2008 to 2012. Th e highest incidence rates occurred in males, black, non-Hispanic service members, service members younger than 20 years of age, members of the Army and Marine Corps, recruit trainees, and those in combat-specific occupations. Incidence rates were higher among service members with homes of record from the Northeast compared to other regions of the U.S. Most cases were diagnosed at installations that support basic combat/recruit training or major Army or Marine Corps ground combat units. Medical care providers should consider exertional rhabdomyolysis in the differential diagnosis when service members - particularly recruits - present with muscular pain and swelling, limited range of motion, and/or the excretion of dark urine (e.g., myoglobinuria) after strenuous physical activity, particularly in hot, humid weather.