The water significantly reduces the impact stress that you would normally feel when doing other exercises such as running. Because of the constant movement (especially if you can’t touch the bottom of the pool or lake) your heart rate will stay elevated, you will build endurance and muscle strength. Because swimming uses a lot of different muscles in your body, it can help you maintain a healthy body weight, heart and lungs.
Other benefits are that swimming can be a relaxing and peaceful way to reduce stress. It improves your balance and posture, your coordination and your flexibility and can be a perfect low-impact form of recovery exercise for injuries.
So grab your bathing suit and towel and head over to the nearest beach or pool!