Effect of acute infectious disease on human isometric muscle endurance.

Capacity for isometric endurance work of different muscle groups was recorded in 32 male patients suffering a variety of acute infectious diseases, predominantly of viral or mycoplasmal aetiology. Recordings were performed after abatement of fever, and 1, and 4 months thereafter. Control measurements took place 1 year later. As a result of the illness the subjects' endurance capacity was reduced to 82.5-86.9% of the control values. Complete recovery was attained later than 4 months after the acute disease. In 21 healthy male control subjects confined to bed for the same period of time as the patients no reduction of endurance capacity was observed as a result of bed rest. The illness induced and long-lasting impairment of static endurance after acute febrile infections might be resated to observations in similar patients of reduced activity in muscle tissue of glyceraldehyde-3-phosphate dehydrogenase being a key enzyme in glycolysis.