The optimal heart rate for a normal person is 60-100 beats/min. The range of heart rate variation is relatively large because it changes with age, gender, day and night temperature difference or emotional changes, but a heart rate of about 60-100 beats/min is the optimal range. For men of the same age, the heart rate is slightly slower than that of women; for older people of the same sex, the heart rate is slower than that of young people; the same person’s heart rate is relatively slower at night when he is asleep and in the morning when he gets up, and it is the fastest time of the day around 13-19 am. In addition, the heart rate changes with the change of body temperature, and the heart rate is also stimulated by sympathetic nerves, resulting in a fast heart rate.