Strictly speaking, aerobic and anaerobic exercise are carried out alternately. Hiit in keep is the mutual switching between anaerobic and aerobic systems, which can achieve better fat burning effect.

HIIT is the abbreviation of high-intensity interval training, which means high-intensity interval training method. It is used to practice cardiopulmonary function and impact speed, and it has obvious effect of reducing fat with other training. This special training method has been popular in Europe and America since it came out, and burning fat and calories with high quality in a short time is very suitable for modern people's lifestyle.

During exercise, breathing and heartbeat accelerate, oxygen content in blood increases, and heat begins to be consumed in large quantities. At the same time, because the intensity of exercise is relatively high, muscles need more energy, so some substances in the body will be anaerobically decomposed to provide energy for exercise. In this process of combining aerobic and anaerobic exercise, fat reduction and shaping are completed at the same time. This fitness method subverts the difference between traditional aerobic exercise and anaerobic exercise, and can reduce fat more effectively through the change of rhythm and the switch of exercise mode.