To clarify the effects of wrist occlusion at pressure of 80mmHg (Occl) and dilution ventilation through neck-hole (DVNH) on thermoregulatory responses during heat load, seven female subjects exercised at heart rate level of 120bpm for 30min at room temperature of 23℃ and 50% relative humidity. They wore experimental garments made of 100% polyester. There was no significant difference of rectal temperature (Tre) in both Occl and no-Occl. Forearm and finger skin temperatures significantly decreased in Occl compared with no-Occl. Suppressed slope of the regression lines showing the relationship between finger skin blood flow (SBF) and Tre in Occl induced compensatory increased slopes of SBF-Tre and sweat rate-Tre in the chest. Skin temperatures in the chest and upperarm were significantly lower in DVNH compared with no-DVNH. There was a tendency of higher slopes of finger and chest SBFs-Tre and chest sweat rate-Tre, and lower shift of the threshold Tre in DVNH. These results suggest that DVNH is effective during less thermal load and suppressed heat loss in Occl at 80mmHg is totally compensated for accelerated SBF and sweat rate in the chest at least.

DESCENTE SPORTS SCIENCE Vol.25/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE