Exercise is not recommended when the body is hot, because the body is already in a high metabolic state when it is hot, and as the body temperature rises, breathing accelerates and the heart rate also accelerates. If you exercise at this time, it will greatly increase the burden on the heart. In addition, the body is in a weakened state when fever is present, and it is likely that safety accidents will occur when exercising under such circumstances, such as inadvertent falls and injuries during exercise. At the same time, patients in the process of high-intensity exercise may induce arrhythmias, and in serious cases, the risk of sudden death. Therefore, exercise is not recommended when the body is feverish, and patients should be advised to rest and drink an appropriate amount of water to maintain the body’s water balance when they are feverish. The body temperature should also be monitored and, if necessary, treated with antipyretic drugs.