| As a major sports space,gyms have a stronge demand under the leadership of the national health strategy and plan.However,the current environmental standards for gyms are not based on exercise.How to make gyms support exercise,comfort and reduce energy consumption at the same time is the main topic of this research.This study conduct in an existing commercial gym,and select 20 young subjects with moderate exercise levels in subtropical regions under five test conditions(Vary temperature conditions: ET*22,24,26 ℃;Use airflow conditions: ET*26 ℃ with high wind speed,ET*26 ℃with low wind speed),perform aerobic exercise(elliptical trainer,cycling)and leg strength training.We record the exercise performance and thermal respones of moderate exercise level trainers under the changes of temperature and wind speed,with the goal of obtaining normal exercise data,not pursue the maximum exercise performance.Under the guidance of supporting exercise,comfort and energy saving,the recommendations for gyms in subtropical regions during summer are proposed to guide the actual situation.The results show that the indoor temperature should be 23.5-24.5 ℃,and the relative humidity should be 40-50%(ET*24 ℃,the indoor radiation temperature is similar to air temperature).In this condtion,exercise intensity of trainers are stable,the overall thermal responses are good,and it has an energy-saving effect.It is also recommended to use wind speed >1.66 m/s,if airflow can be used in the gym,the indoor temperature is 25.5-26.5 ℃,and the relative humidity is 40-50%(ET*26 ℃,when the indoor radiation temperature is similar to the air temperature),the exercise performance will be stable,and the thermal responses will be great.Aerobic exercise performance at ET*22-26 ℃ will not stimulate or damage,but exercise intensity usually increases slightly with the rise of temperature.Trainers have a stable mechanism that coordinate exercise intensity and exercise time to ensure that the volume of activities are basically constant.Male’s leg strength training performance is not affected by this temperature range,but female complete less training at ET*22 °C,and the exercise effect is weakened.After using airflow,the exercise intensity level of improving aerobic exercise is slightly higher,and there is no difference in exercise performance between conditions.During strength training,there is no significant difference in the external load between conditions,but the internal load are different in some conditions.Trainers can maintain a great thermal responses at ET*24 ℃,aerobic exercise and strength training have poor thermal responses at ET*26 ℃,but with the use of airflow,thermal responses are improved.The thermal responses are similar at ET*22,24 ℃,while using airflow.Daily trainers have different perceptions and needs of thermal environments from sitting or working people.They prefer cooler temperature and higher wind speeds.MET value is not the only variable for predicting thermal comfort during exercise.PMV will overestimate the temperature requirements of exercisers and cannot be used to predict thermal comfort during aerobic exercise and weight training. |
