Elevation of creatine phosphokinase in young men after recreational exercise.

Twenty healthy male volunteers were divided into four groups for a period of recreational physical exercise. Standard blood chemistry determinations were made before exercise and on the two subsequent days. Creatine phosphokinase (CPK), SGOT, and lactic dehydrogenase levels were transiently elevated, but the change was considered significant only in the CPK level after certain types of exercise. Persons having these determinations performed should be questioned about recent physical exertion in the event of abnormal laboratory results.