Cardio Exercise Definition

Cardiovascular exercise, commonly referred to as aerobic exercise or simply "cardio," is physical activity that causes the body to adapt to more efficient movement of oxygen through the circulatory system. By causing the body to more quickly move and increasing a person's heart rate, cardiovascular exercise has a variety of effects on the body.

Intensity

Cardiovascular exercise intensity is the degree of physiological stress placed on the body due to aerobic exercise. It is measured by the percentage of a person's maximum heart rate that is used for the exercise. Low-impact cardiovascular activity uses approximately 55 percent of maximum heart rate. Activities performed by a highly conditioned athlete use more than 85 percent of maximum heart rate. The average individual should use between 55 and 85 percent of maximum heart rate when exercising, according to the Aerobics and Fitness Association of America.
The American Heart Association recommends different intensities of cardiovascular exercise, depending on an individual's age, general health and fitness goals. Seniors, women who are pregnant and other special populations should only engage in low-impact cardiovascular activities and seek a doctor's clearance before exercising.

Types of Cardiovascular Exercise

To qualify as a cardiovascular exercise, an activity must consume oxygen and increase the exerciser's heart rate and blood pressure. Common types of cardiovascular exercise include walking, jogging, hiking, running, in-line skating, biking, rowing and swimming. Aerobics classes, such as step, cardio boxing, aqua, slide, high-low floor aerobics, cycling and boot camp, also allow for cardiovascular exercise, as do sports like boxing, tennis, soccer, volleyball and basketball.
Walking, aqua aerobics and high-low floor aerobics are considered low-impact cardiovascular exercise. Step, cardio boxing, boot camp and most competitive sports are high-impact cardiovascular activities.

Physiological Benefits

Regular cardiovascular exercise has been shown to create better cardiac output---the amount of blood the heart can pump---and also increase the ability of muscles to extract and use oxygen from blood. As a result, the body needs to take in less oxygen to do the same amount of work. All of these things cause health benefits for the exerciser.
Exercise can help control blood lipid abnormalities, diabetes and high blood pressure. Cardiovascular exercisers tend to have fewer cases of death due to heart-related issues and lead overall longer lives.

Psychological Benefits

There is a strong correlation between cardiovascular exercise and psychological well-being. Regular aerobic exercisers tend to perform better on cognitive tests and have healthier reactions to stress. Many studies have shown that aerobic exercise reduces depression in people who are healthy as well as those who suffer from cardiac disease or extreme clinical depression. It has also been shown to increase self-esteem and make exercisers less likely to engage in unhealthy type A behaviors.

Effects on Body Composition

Because cardiovascular exercise causes the body to use more calories and increases a person's metabolism, it has a strong positive effect on weight loss programs, particularly when combined with a low-fat diet. Aerobic exercisers have been shown to have less fat in their stomach region and around their hearts as well as a lower amount of total body fat, which greatly decreases the risk of heart disease.
The muscles of cardiovascular exercisers are also better able to utilize fats during exercise, thereby preserving intramuscular energy storage.