Human adipose tissue blood flow during prolonged exercise II.

Subcutaneous and perirenal adipose tissue blood flows (ATBF) were measured by the 133Xe washout method before, during and after 4h exercise on a bicycle ergometer. The load corresponded to about 50% of VO2 max (i.e. about 1.7l/min). Subcutaneous and perirenal ATBF increased at an average to 3--400 and 700% of their initial control values respectively. In six of nine measuring sites ATBF remained increased in the hour following work. During work plasma glycerol concentrations increased 8 fold. The core temperature increased 0.9 degree C, skin temperature did not change significantly. During passive elevation of body temperature (core temperature +1.5 degree C; skin temperature +3 degree C) neither subcutaneous ATBF nor plasma glycerol concentrations changed significantly. It is concluded that the increase in subcutaneous ATBF during exercise is not a reaction to increased body temperature.