EFFECT OF GENDER ON FOREARM MUSCLE METABOLISM 535

Abstract

To address whether significant gender differences exist for glucose and protein metabolism in human forearm, we compared foream blood flow, glucose, lactate and phenylalanine balances, oxygen uptake and the rates of protein synthesis and degradation between postabsorptive men (n=40) and women (n=36).Table To address whether these differences might result from male/female differences in muscle mass, forearm composition was measured (MRI × 16 cuts) and muscle mass estimated from a reconstructed 3D image in 17(8male/9female) subjects. In women the% of forearm composed of adipose was greater and% muscle mass less than men. In these subjects, neither the balances for glucose, phenylalanine and oxygen nor rates of protein synthesis or degradation differed between males and females when expressed per 100ml muscle. Table Conclusion: Cross sex comparisons of metabolic variables must accommodate differences in tissue composition. These data suggest that once corrected for muscle mass there may be no gender difference in forearm muscle metabolism of glucose, protein, or oxygen.