Why does heart rate increase during exercise? There are two reasons for this phenomenon:
- When you exercise, your muscles require much more oxygen, so the heart works harder to send these red blood cells to your muscles, thus increasing your heart rate. Without the extra oxygen, muscles will not be able to produce contraction energy, and will not work properly during a workout. Your lungs send oxygen-rich red blood cells to your heart. From your heart, these oxygenated blood cells are directed to areas of the body they are needed. Your muscles need this extra oxygen for energy. The basic energy molecule, called ATP is created when mitochondria mix oxygen with fat and glucose. When you are exercising, your heart needs to beat at an increased speed to provide your muscles with the oxygen to produce this energy creation.
- Another reason your heart rate increases during exercise is the body’s natural cooling effect. When your body gets too hot, your heart needs to work even harder to send blood to the skin. This allows the body to cool itself naturally and still supply the muscles with the required energy it needs to continue to exercise.
You need oxygen in every area of your body. The heart supplies this when it pumps oxygen-rich red blood cells to each area. The heart needs to work harder when a specific area, or areas, of the body need an extra supply of oxygen.
You may notice that your heart beats faster and harder when you first begin exercising. If you have been sedentary for a while, your heart has not had to work so hard and will need to give more effort in doing so. As you exercise more and more, your heart will become stronger and can begin to pump more blood without working so hard.
Other factors of heart rate increase while exercising are food intake before you exercise, what your emotional state is at that time, and the type of exercise. Different types of exercises such as continuously exertion during exercise or interval exercise will vary your heart rate.