One of the best all-around exercises, swimming increases both cardiovascular and muscle strength. There is hardly any stress on your body’s joints, because water turns you into a kind of weightless underwater astronaut, making your every movement an easy, flowing one. But water also offers resistance that helps you build muscle strength and tone.
Doing laps in a pool — no matter what the stroke — is excellent exercise. You can also “take a walk” underwater or perform calisthenics like leg lifts or arm circles. Research shows that water actually offers an equal aerobic workout in less time than one on dry land. A half-hour of walking in water equals the energy output of a two-hour walk in the woods, one study showed. Make sure you’re about chest deep (to benefit from the resistance) and simply go for a stroll.