Personally, I think that if the temperature is too high, it will affect exercise. Especially at the high temperature of 40℃, the body metabolizes quickly and sweats when standing still. Needless to say, you can't keep running at room temperature. If you sweat more, your physical strength will definitely be exhausted in advance and more trace elements will be lost. Strength training will also be affected. Heavy weight training at high temperature can cause dizziness and high blood pressure. If the supplement is not enough, there will even be dehydration and heatstroke. This is my personal summary, because I have personally experienced fitness for more than one year, and I also have personal experience. With global warming, I feel particularly hot this summer, and I hardly jog outdoors all summer. The most suitable fitness temperature is 26 degrees Celsius. The gym will provide such a temperature environment. Of course, it is wise to turn on the air conditioner at home to create a good fitness environment for yourself.