Stretching heartbeat acceleration may be due to just do high intensity exercise, stretching when breath holding and arrhythmia. 1. Having just done a high-intensity exercise: If you have just finished a high-intensity exercise, your heart will beat faster. When stretching, the heartbeat may still be in an accelerated state. Therefore, it will be manifested as fast heartbeat when stretching. 2. Breathlessness when stretching: some people will hold their breath when stretching, which will make the body short of oxygen, which will stimulate the heart to increase the strength of circulating blood in order to ensure the normal supply of oxygen to the body, which will lead to a faster heartbeat. 3. Arrhythmia: The heartbeat of patients with arrhythmia loses its normal rhythm and may beat faster or bradycardia. When the patient stretches, it produces a certain stimulation to the heart, which may cause the heart to beat faster. If stretches the heart to speed up the attack frequently, it is recommended to go to the regular hospital in time to find out the cause, and then accept the professional doctor to treat the cause.