Swimming is a cardio exercise because it raises your heart rate, which increases the circulation of oxygen throughout your body. Like other cardio exercises, swimming regularly will strengthen your lungs and heart, tone your muscles, improve your mood, burn calories and lead to fitness. The key is to swim vigorously at a pace you can maintain for a long period of time.
Function
Swimming is an effective cardiovascular exercise because it incorporates full body movement for long periods of time. Swimming also burns many calories. For example, a 125-lb. person who swims laps vigorously for 30 minutes burns 300 calories, according to Harvard Medical School. If you weigh more, you'll burn more calories because your body must work harder to keep you moving. A person who weighs 185 lbs., for example, burns 444 calories by swimming laps vigorously for 30 minutes.
Swimming Basics
If you don't know how to swim, take swimming lessons and learn the basic strokes. Treading water and dog paddling are the simplest. More advanced strokes, such as the crawl, develop controlled breathing and movements. During your initial workouts, practice your swimming strokes so that you perform them correctly. Avoid bad habits, such as holding your breath while swimming, which will quickly lead to fatigue. Ask a swimming coach to help you develop proper breathing techniques and controlled, efficient movements.
Improving Endurance
If you're a beginner, you might find it difficult to swim many laps without tiring. Use a kickboard or other flotation device to help you finish your workout. For example, start off your workout by performing as many full laps as you can. Once you tire, complete your workout with a kickboard. If possible, finish your workout by performing one more lap without any assistance. Don't worry if it takes a long time for you to develop the muscle endurance necessary to swim multiple laps. If you swim regularly, your endurance and strength will increase.
Considerations
Swimming is a suitable cardiovascular exercise for people who have difficulty participating in such high-impact aerobic activities as jogging or aerobic exercise classes. When you are in the water, you are buoyant, which effectively reduces your weight by 90 percent. For that reason, swimming is less stressful on your joints while still providing a vigorous, calorie-burning exercise.
