March hemoglobinuria; report of five cases in students at Ohio State University.

• Dark-colored urine and painfully swollen muscles were the essential complaints of five otherwise healthy, athletic students at the Ohio State University. The manifestations included albuminuria in all cases; in the most severe case, casts and red blood cells were found in the urine and the temperature went up to 100F (37.8 C). The common causative factor proved to be recent exhausting muscular exercise, and recovery was spontaneous. The condition is not believed to have been identical with that described by other authors as march hemoglobinuria but a new syndrome termed "exercise myohemoglobinuria."