Effect Of Sportswear Cover Area On Thermoregulation During Running In Warm And Hot Environments

During exercise,body heat production increases and sweat rate also increases.Evaporation is the main way of heat dissipation in the human body.Not all the amount of sweat is effective in cooling,sweat simply dropping down from the body surface makes no contribution.Garments can absorb sweat before it drops.The sweat held in garments can then evaporate from its outer surface and thus increase evaporation rate.This implicates that the area of garments covering the body can make difference on thermoregulation.Therefore,this research is aimed at the effect of the different cover area sportswear on the thermal physiology of the subjects in a warm and hot environment.This research selected three sports ensembles with the same fabric and tights.Three sports ensembles respectively different cover area: Long,a long sleeve T-shirts and a pair of long pants;Short,a short sleeve T-shirts and a pair of short pants;Brief,a brief.The measurement of sportswear thermal insulation and evaporative resistance in the static and dynamic.Five male subjects respectively wore three sports ensembles participated running trials in warm and hot environments(22oC,60%RH;0.4m/s airflow and 30oC,44%RH;0.4m/s airflow).The mean skin temperature(Tsk),rectal temperature(Tre),heart rate(HR),and sweat amount were measured,subjective evaluation was record in researchIt was found that:(1)In warm and hot environments,the rise of Tre of Long was lower than other two sports ensembles,the rise of Tre of Long respectively maximum can be reduced : 0.24??0.10?.(2)In warm environment,wore Long can be reduced the amount of sweating,the maximum can be reduced by 80 g.(3)In warm and hot environments,the greater the coverage area,the greater the mean skin temperature.In warm environment,Tsk of three sports ensembles are quite different,about 2?;In hot environment,Tsk of three sports ensembles are smaller,about 0.5?.(4)In warm environment,HR of Long is slightly higher than HR of Short and Brief,about 10 bpm.In the heat environment,HR of different cover area is almost identical.In the warm and hot environment,the larger the cover area is,the lower the dry heat dissipation of the human body.The higher Tsk and the larger the coverage area,the lower the Tre and the larger the evaporative heat dissipation.The effect of increasing cover area on reduction of Tre is greater in warm environment,increasing the cover area in warm environment will increase the HR.It due to the sweat amount is higher in hot environment than warm environment,when the sweat rate is higher than evaporation rate,no matter the cover area is increased or not,the sweat has evaporated on the surface of the body or clothing.Increased cover area can help the body to reduce the Tre.