1, primary formula: for people in poor health. Target heart rate =(200- age) *(60%~80%)60%~70% is mainly used for reducing fat; 70%~80% is mainly used to improve cardiopulmonary function.

2. General formula: for the general population. Target heart rate =(220- age) *(60%~80%)60%~70% is mainly used for reducing fat; 70%~80% is mainly used to improve cardiopulmonary function. 3. Caffeine formula: suitable for people with high physique. Target heart rate =(220- age-resting heart rate) *(65%~85%)+ resting heart rate 65%~75% is mainly used for reducing fat; 75%~85% is mainly used to improve cardiopulmonary function. Besides,

Adding a little self-feeling is an important indicator to master the amount and intensity of exercise, including mild shortness of breath, feeling a little heartbeat, slight fever, reddish complexion and sweating, indicating moderate exercise;

If there is obvious palpitation, shortness of breath, fever, dizziness, sweating and fatigue, it means that the exercise exceeds the limit;

If your exercise stays at the level of "face-deadening, heart-beating" and your heart rate is too far from the "bull's-eye rate", it means that your exercise can't achieve the purpose of enhancing your physique and endurance, and you need to add more.