Urinary Excretion of Mucoproteins and Adrenal Corticosteroids During Rest and Exercise. Relation to Urine Volume and Physical Fitness

¹ From the Medical Nutrition Laboratory, United States Army, Denver, Colorado

The interrelationships in healthy young adult males among 1) Harvard step test score, 2) urinary excretion rates of a) mucoprotein constituents (nondialyzable nitrogen and hexosamine) and b) 17-hydroxycorticosteroids and 3) urine volume have been analyzed statistically by the technique of partial linear correlation for conditions of rest and submaximal work. At rest there was a marked dependence of metabolite excretion upon urine volume, without a significant relation to step test score. During exercise the volume dependence decreased, while the correlation of metabolite excretion with step test score became significant. It is hypothesized that metabolite excretion rates during exercise are maintained at the highest levels in those individuals whose cardiac and renal circulatory responses are most efficient.