1 Excessive exercise and fitness exercise will increase the fatigue of the human body and affect the function of the body, especially when the energy consumed by physical exercise is unbalanced with the energy absorbed by the body, it will affect the normal metabolism of the body, leading to the decline of the body's immunity and resistance, and the cold virus will easily take advantage of it, leading to a cold and fever.

2 Weather reasons In winter fitness, especially in some outdoor fitness programs, some people pretend to wear shorts or feel very hot during fitness. When they sweat, they will take off all their clothes. When they are blown by the cold wind, they are prone to catch a cold and have a fever.

Taking a cold bath to do exercise immediately after fitness, the body's metabolism is vigorous, and the body temperature rises, which leads to the expansion of blood vessels on the skin surface, large pores and increased perspiration, thus fully dissipating heat. It takes some time for this phenomenon to return to its original state after exercise. If you take a cold shower immediately, the skin blood vessels will contract immediately because of cold stimulation, and the pores will close quickly, resulting in a lot of heat in the body, which will hinder the normal regulation of body temperature and weaken the body's resistance to bacteria and viruses originally hidden in the nasal cavity.

There are people with colds in the gym. Many gyms are poorly ventilated or basically unventilated, which is conducive to the spread of cold viruses. If there are one or two people who have a cold in the gym, there may be infection, cold and fever.