There’s something deeply re-energising about gliding through the water, whether it’s chlorine or salt water.

You come out feeling relaxed and buzzing. Renewed. But you can’t help wonder… was it a good use of your time? Would you have been better off going for a run or doing an exercise class? And what about that thing your friend says that swimming makes you put on weight?

Don’t worry! Swimming is an amazing form of exercise, and wonderful for your physical and mental health. Here’s why:

1. It strengthens all your muscles

Swimming gives you a full-body workout. It works muscles throughout your entire body, including your legs, glutes, arms, neck, shoulders and core. Remember, water is 800 times denser than air, so it gives you a great resistance workout.

2. It lowers stress and helps with depression

Ever got out of the pool and felt the weight of the world had lifted off your shoulders? You didn’t imagine it. Swimming can induce a relaxation response similar to yoga.

The relaxation response is thought to be due to the constant stretching and releasing of your muscles, combined with deep rhythmic breathing. Plus, the feeling of being away from everything in the water (where your phone can’t beep at you) can help relieve stress.

3. It burns calories

Swimming can burn equal or greater calories than running, although it depends on how hard and fast you go.

Running for 10 minutes burns around about 100 calories (depending on your weight and speed).

With 10 minutes of swimming, you burn 60 calories with breast stroke, 80 calories with backstroke, 100 calories with freestyle, and 150 with butterfly stroke.

4. It regulates blood sugar

A 2016 study found that short bursts of high-intensity swimming three times a week can balance blood glucose. That’s great news for those with diabetes or it you are at risk of diabetes.

5. It helps you live longer

No, really. Researchers at the University of South Carolina looked at 40,547 men, aged 20 to 90, for over 32 years. They found those who swam had a 50 per cent lower death rate than runners, walkers, or men who didn’t exercise.

What about just submerging yourself in water? Is that good too?

Yes. And there’s different benefits for cold vs warm water. Immersing yourself in very cold water, that is around 15 degrees Celsius, can help with pain, muscle recovery and boosts your metabolism. Some studies suggest it can reduce symptoms of depression.

Ice baths take this idea up a notch. The “Wim Hof method” promotes ice baths or very cold showers combined with deep breathing. Wim Hof says it stimulates your vague nerve, which boosts your parasympathetic nervous system and affects conditions such as anxiety and depression.

Lowering yourself into warm water is a gentler way to promote relaxation. Research from Washington State University finds that warm water immersion, like a bath, balances your nervous system and helps lower stress.

“The effects of aquatic immersion are profound, and impact virtually every body system,” says Dr Bruce Becker, director of the National Aquatic & Sports Medicine Institute at Washington State University.