Running in place may cause knee damage, lead to thickening of calves and affect the respiratory system if the movement is not standardized. 1. Knee injury: because running in place is likely to be unable to stretch the limbs properly, it may repeatedly rub the knee, resulting in knee damage, and it will affect the blood circulation around. Many people feel pain in their legs after running, so they can apply appropriate hot packs. 2. Thickening of calves: Running in place may have certain deficiencies, which may not achieve the purpose of exercise, which will lead to thickening of the calves, affecting the overall aesthetic. Therefore, it is generally recommended to run outdoors frequently, and also pay attention to the amount. 3. Impact on the respiratory system: because running in place space is relatively narrow, air circulation is not good, so in the process of running with insufficient oxygen, it may damage the respiratory system, easy to cause chest tightness, rapid heartbeat. If you feel short of breath and fast heartbeat, you should stop exercising as soon as possible and take rest. Although running in place can exercise your body, it has many shortcomings, so if you want to run to exercise your body, try to choose to go to a wide place.