Swimming is an effective form of exercise, a competitive sport, a skill that could save your life and is suitable for young and old exercisers alike. As the water supports your body weight, swimming is a low- to no-impact exercise, though the breaststroke can have a negative effect on your lower back and knees, and the freestyle and butterfly can be hard on your shoulders.
Cardiovascular Fitness and Health
Swimming uses most of your large muscles and many of your smaller ones. This increases your need for oxygen. Oxygen is taken into your body by your lungs and then pumped around the body by your heart through your blood vessels. Regular swimming strengthens your respiratory muscles, improves lung function, strengthens your heart and improves the elasticity of your blood vessels. The physiological changes result in increased aerobic fitness and cardiovascular health.
Improved Muscular Endurance
The ability of your muscles to perform large amounts of work without fatigue is called muscular endurance. Muscular endurance is the result of an increased ability to keep your muscles supplied with essential oxygen and an improved ability in clearing away lactic acid. This is achieved through the formation of new capillaries, which allows greater amounts of oxygen to be delivered to your muscles and also facilitates the removal of lactic acid. Long-distance swimming has the greatest effect on muscular endurance, while sprint swimming develops strength and power.
Effective swimming requires that you use a smooth and efficient technique. Poor technique, where limbs flail powerfully but ineffectually, will result in considerable energy expenditure but relatively little forward travel. Successful swimming requires and develops intermuscular coordination. Novice swimmers often find their movements unwieldy and lack grace, though they are trying hard. More advanced, proficient swimmers are simply better able to coordinate their movements for maximum effectiveness. This improved coordination takes time to develop. It is a long-term effect of regular swimming and is the reason a less fit but technically proficient swimmer can beat a fit but uneconomical swimmer.
Enhanced Joint Mobility and Health
Joint mobility is a term used to describe how freely your joints move. The more mobile a joint, the greater the effective range of movement. Swimming uses large ranges of movement that enhance joint mobility. In addition, the rhythmical action of swimming increases the production of synovial fluid within your joints. Synovial fluid lubricates and nourishes your joints from within. As swimming is non-weight bearing, your joints are not placed under any form of jarring impact, unlike jogging or running. Instead, your joints are exercised safely and effectively through a wide range of movement that can enhance their long-term health.