"HIIT" is the abbreviation of high-intensity interval training. This kind of training is a short and effective training method, which adopts tabata, that is, high-intensity exercises are nested in a short recovery period and repeated. The purpose of HIIT training is to increase the heart rate and stimulate the body's metabolic rate in a short time, so as to achieve the effect of burning fat quickly, and at the same time enhance the training effect of cardiopulmonary function and muscle endurance.