The responses of glabrous and nonglabrous skin microcirculation to graded dynamic exercise and its recovery

This study investigated the responses of skin blood flow (SkBF) in glabrous and nonglabrous skin to graded submaximal dynamic exercise and its recovery. We enrolled eight healthy young men with comparable maximal oxygen uptake (VO2max). Laser-Doppler flux (LDF) was assessed on the finger pulp (glabrous site) and the volar forearm (nonglabrous site) simultaneously with skin temperature, heart rate and blood pressure; cutaneous vascular conductance (CVC) was calculated. Subjects were monitored before (baseline), during and 25 minutes after incremental cycling. CVC in the pulp decreased with the onset of exercise (0.53±0.09AUmmHg-1 vs. baseline 1.23±0.25AUmmHg-1, p = 0.006), and persisted low until exercise cessation, whereas CVC in the forearm started to increase at 60% of subjects' VO2max, attaining its maximum at the highest exercise load (0.44±0.11AUmmHg-1 vs. baseline 0.12±0,03AUmmHg-1, p = 0.017). In the recovery, CVC in the pulp attained a higher plateau value compared to baseline (1.51±0.22AUmmHg-1, p = 0.021), interrupted by abrupt transient falls of CVC. On the forearm, CVC subsequently returned to its baseline. SkBF of glabrous and nonglabrous sites adjust in an opposite manner to graded exercise load and also differ during recovery.