A pulse rate of 100 means a fast heart rate, which may be due to physiological reasons or diseases such as anemia and pulmonary heart disease. A pulse of 100 beats per minute falls within the upper limit of the normal heart rate. Rapid heart rate levels can be seen for physiologic reasons, such as emotional excitement, excessive anxiety, and rapid exercise, and the cause of the rapid heart rate is related to sympathetic nerve excitation. A pulse rate of 100 beats per minute can also be seen in pathological conditions, such as anemia. In anemia, hemoglobin and red blood cells are reduced, and there is a relative lack of oxygen in the body, and the heart rate will reactively increase. Tachycardia can also occur in patients with pulmonary heart disease, due to the decline in lung function, the body is in a state of hypoxia, the heart rate will be compensatory increase. There are many other reasons for fast heart rate in the clinic, such as hyperthyroidism, arrhythmia and other diseases, the symptoms are obvious, we should go to the hospital, to clarify the specific cause of the disease, physiological reasons, no special treatment.