Influence of isometric exercise on blood flow and sweating in glabrous andnonglabrous human skin

The distribution of the reflex effects of isometric exercise on cutaneous v asomotor and sudomotor function is not clear. We examined the effects of is ometric exercise by different muscle masses on skin blood flow (SkBF) and s weat rate (SR) in nonglabrous skin and in glabrous skin. The latter contain s arteriovenous anastomoses (AVAs), which cause large fluctuations in SkBF. SkBF was measured by laser-Doppler flowmetry (LDF) and reported as cutaneo us vascular conductance (CVC; LDF/mean arterial pressure). SR was measured by capacitance hygrometry. LDF and SR were measured at the sole, palm, fore arm, and ventral leg during separate bouts of isometric handgrip (IHG) and isometric leg extension (ILE). CVC and its standard deviation decreased sig nificantly during IHG and ILE in the palm and sole (P < 0.05) but not in th e forearm or leg (P > 0.05). Only palmar SR increased significantly during IHG and ILE (P < 0.05). We conclude that the major reflex influences of iso metric exercise on the skin include AVAs and palmar sweat glands and that t his is true for both arm and leg exercise.