To the Editor.
—This letter is concerning the article entitled "March Myoglobinemia: A Hazard to Renal Function" by Melamed et al published in the July Archives (1982;142:1277-1279). Melamed et al noted that episodic bouts of progressively intense exercise by soldiers in a training program may cause deterioration of renal function. Endogenous 24-hour creatinine clearance was serially determined before the start of training and on days of hikes measuring 10, 30, and 45 km on weeks 2, 5, and 8, respectively. After a slight rise on the day of the first hike, creatinine clearance fell with each successive hike and was about half normal on the last one. During each hike, there appeared chemical evidence of minor rhabdomyolysis and myoglobinuria that are well known to occur under such conditions.Melamed et al suggested that myoglobinemia and myoglobinuria, although subtle, were probably responsible for the apparent decline of creatinine clearance. They cautioned