Submaximal exercise during intravenous hyperalimentation of depleted subjects

The peripheral nitrogen wasting and loss of functional capacity caused by the malnutrition of disease and the immobilization of hospitalization may not be readily reversed by refeeding alone. In order to examine submaximal exercise as an adjunctive anabolic stimulus to intravenous refeeding (IVF) in depleted subjects, 14 volunteers were studied in the postabsorptive (PA) state, after 10 days of total starvation, and again after 10 days of nutritional repletion with I.V. feedings. The subjects were randomized to one group that received IVF alone and one group that performed 1 hour of submaximal (51% of VO2max) stationary bicycle exercise daily during IVF. The exercised group was not significantly different from the nonexercised group in urinary nitrogen balance, resting energy expenditure, extremity amino acid flux, or maximal oxygen consumption. Acute exercise did not induce significant derangements in electrolytes or counter-regulatory hormone concentrations. Ten days of submaximal exercise does not appear to be detrimental in this population recovering from moderate hospitalized malnutrition, but additional anabolic stimulae may be needed for improvements in protein accrual or functional capacity.