When running, the beating speed of human heart will increase rapidly, which is normal, because when running, muscles need more nutrition, and more nutrition needs faster blood flow speed, so blood needs faster heart beating, because the heart is like a pump of human body. The stronger its strength, the stronger its output capacity and the happier it beats, so the faster the natural blood will flow and the more nutrients the muscles will get, so the heart will beat faster during exercise.
Usually, when your mood is stable and your body is calm, the measured heart rate is of reference value. Normally, the normal slope should be around 70. If you have arrhythmia, it may not be the heart rate but the heart itself. This needs something more professional. Then when your heart rate exceeds 80 times, it proves that your heart rate is a little fast, because the normal person's heart rate is 60 to 80 times. If you are over 80 years old, there is a problem, because if you don't exercise, your body doesn't need so much nutrition. If you don't need so much nutrition, your heart will still beat fast, which proves that your heart is weak.
The beating ability of the heart is very weak. To put it another way, your heart can squeeze out less blood at a time than other people's hearts. For example, others can squeeze out 20 ml of blood at a time, and you can only squeeze out 15 ml at a time. That body can only make the heart beat faster in order to ensure the supply of nutrition, but you should know that there is a limit to the beating of mammals. When the number of heartbeats reaches the limit, your heart will.