The influence of an active microclimate liquid-cooled vest on heat strain alleviation

Abstract

This research was performed to test the effectiveness of the microclimate body cooling system which belongs to the group of active systems with liquid-cooled technology. The liquid cooling vest efficiency was observed concerning the physiological fitness of the standard protective set used in specific environmental conditions which imply increased thermal strain of the test subjects. Experimental results from the research are based on the examinations carried out in a thermo-physiological laboratory. Ten healthy male volunteers ? test subjects aged (23.4 ? 2.4 years, weight 74 ? 7 kg, and height 184 ? 9 cm) were exposed to thermal strain testing (40 ?C temperature, 40 ?3 % relative humidity, without wind) and simultaneously to physical effort caused by walking on the treadmill at a speed of 5 km/h, during 45 minutes. Tests were performed in two variants: without any cooling system and with the KewlFlow Circulatory Cooling Vest with Cooler Kit. Throughout heat exposure, the subject?s body core temperature (tympanic temperature ? Tty), mean skin temperature, Tsk, and heart rate were measured. Furthermore, sweat rate was calculated in order to determine all changes in the water and electrolyte status. Experimental results confirm that the results of this study have recognized the benefits of a liquid-cooled vest in lowering the thermal strain.