Cardiovascular exercise (or "cardio") refers to any type of activity that involves the continuous and rhythmic movement of large muscle groups. Cardio exercise strengthens the heart and lungs and improves the cardiovascular system’s ability to deliver oxygen to the body.

All types of exercise fall into one of two categories: anaerobic and aerobic. Anaerobic exercises are those that do not significantly raise the heart or breathing rate. Strength training and stretching are two examples of anaerobic exercises.

Aerobic exercises are activities that require a great deal of oxygen. The term aerobic is often used interchangeably with the term cardio. Cardio activities include a vast number of exercises, including running, kickboxing, rowing, brisk walking and swimming.

Many people associate "aerobics" with a type of group dance performed to high-energy, exercise-inspiring music. Whether swimming laps alone or exercising in a group, the purpose of cardio exercise is the same: To strengthen the heart and cardiovascular system, improve stamina and, for many people, to lose weight.

This article explains how cardio exercises benefit the body and offers a few pointers to help an individual get started. Always consult a physician before beginning any exercise program.