Exercise is beneficial for strengthening the cardiovascular system, and the body typically responds by raising your heart rate, expanding your breathing patterns and increasing how much you sweat.

Increased cardiovascular fitness causes real physical changes in the structure of the heart. The muscles in the heart wall thicken, and the heart pumps more blood with each beat. That increased efficiency means an athlete's resting heart rate falls to a level that could indicate trouble in a nonathlete.

Your maximum sustainable heart rate varies depending on your overall fitness level. A physically fit person can sustain a high heart rate longer than a beginning or intermediate cyclist.

Although a racing heart following exercise can be unsettling and frightening, it is usually a harmless condition. However, because it is such a disturbing symptom, it is important to understand how to treat it–and to know when to seek medical attention for it.

Just as it does during any type of aerobic activity, your heart rate increases when you lift weights. That being said, heart rate is not as good an indicator of how well your weight training workout is going as it is for aerobic exercise. J. Andrew Doyle, Ph.D.

Your cardiac output is the amount of blood that your heart pumps each minute. The two principal factors that determine your cardiac output includes the number of times your heart beats each minute -- which is your pulse; and the actual volume of blood pumped out with each heartbeat -- which is your stroke volume.

Most people are familiar with how their bodies feel during exercise; the heart beats faster and it becomes harder to breathe. This is a response to increased work by the muscles and an escalating need for oxygen throughout the body.

It will not hurt a healthy person to take a hot or a cold shower, but either one can increase your heart rate. Another factor that can add to this is worry about getting to work on time and the problems you have to deal with when you get there. Hurry makes you move faster, and this too can increase your heart rate.

Your heart rate should be high when you exercise, but it shouldn't stay high after you stop. Your heart rate should begin returning to normal immediately after exercise, but it can take hours to fully recover. Check your heart rate recovery and your resting heart rate to assess your health.

Belly fat is a dangerous risk factor for cardiovascular disease. Here's how to calculate your heart rate for burning belly fat with exercise.

Exercise boosts your blood pressure and heart rate temporarily and is one of the best ways to promote a healthy heart. But if you experience a drop in your heart rate while exercising, it could signify either a minor, temporary problem or a more serious underlying cardiovascular condition.

Your heart rate automatically increases when you exercise. It does so to adapt to the increase in activity. Based upon your age, your heart rate varies from one age group to the next. An unfit person has a higher heart rate than a fit person.