Swimming brings many of us so much joy. It doesn’t seem to matter whether you're doing an endurance session, a technical workout or an interval training, the feeling remains similar - it makes you happy. The reason why you are feeling this is due to changes in your brain's chemistry, let us explain precisely how that works... 

1. Stress reliever
During swimming you stretch, tighten and relax your muscles while simultaneously breathing in a rhythmic pattern, very similar to yoga, and this has a tranquilizing effect on you. In addition, swimming stimulates the release of brain chemicals such as serotonin that influence your mood and produces a stress-reducing hormone, which helps control the brain’s response to stress and anxiety. Therefore just a short swimming session can already be very stress relieving. 

2. Happy hormones 
Swimming stimulates the release of a brain chemical called endorphins which reduce the perception of pain and as a side effect makes us feel happy and gives us this sense of a ‘natural high’, also known as the ‘runner’s high’, which is a feeling of relaxed euphoria, excitement and enjoyment, hence the wonderful feeling after swimming. 

3. Brain health
Exercise in general increases blood flow to the brain, however during swimming this effect is magnified due to the fact that you're submerged into water. A study found that immersion in a pool increased blood flow to the brain, in the study the brain blood flow was greater when participants immersed themselves into a pool filled with water up to the height of the heart, compared to when they weren’t immersed into the pool. The pressure associated with immersion into water is causing this amplification. A steady blood flow brings oxygen and nutrients to the brain, and carries carbon dioxide and toxins away from the brain. This is essential for optimal brain function and mental health. Besides poor brain blood flow and circulation is linked to mental illnesses. The greater brain blood flow while swimming builds a healthy brain and thus a happy brain.

4. Learning a skill 
Swimming is a complex movement pattern in which communication between the two sides of the brain is necessary. When a swimmer is working on technical drills to build stroke accuracy the communication between the two brain sides will develop. This growth will improve cognition and learning. Some studies found that those who learn to swim earlier reach better physical, cognitive, coordinative and linguistic development compared to those who learn swimming later on in life. Furthermore learning a new skill such as swimming can be a positive distraction, bring fulfillment and build our self confidence. Altogether, working on your technique while swimming seems to have a very satisfying effect on you.

5. Blue color 
Lastly, the blue color of water seems to have a calming effect. In studies where colored spaces were matched to emotional facial expressions, the blue color was frequently matched with neutral facial expressions representative of relaxation, calmness and peacefulness. Therefore just looking at the blue water can make you more calm and peaceful. 

Although we never really consider the mental benefits of swimming, we all experience it. So the next time you feel the joy after a swim session you can show appreciation to your brain chemicals which prove how mentally beneficial swimming really is. 

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