When you start exercising, your brain recognises this as a moment of stress. As your heart pressure increases, the brain thinks you are either fighting the enemy or
fleeing from it. To protect yourself and your brain from stress, you release a protein called
BDNF (Brain-Derived Neurotrophic Factor).
This BDNF has a protective and also reparative element to your memory neurons
and acts as a reset switch. That’s why we often feel so at ease and things are clear after exercising and eventually happy.
At the same time, endorphins, another chemical to fight stress, are released in your brain. Your endorphins main purpose is to minimize the discomfort of exercise, block the feeling of pain and are even associated with a feeling of euphoria.
New York Times best-selling author Gretchen Reynolds has written a whole book about the subject matter titled “The first 20 minutes”. To get the highest level of happiness and benefits for health, the key is not to become a professional athlete. On the contrary, a much smaller amount is needed to reach the level where happiness and productivity in every day life peaks:
“The first 20 minutes of moving around, if someone has been really sedentary, provide most of the
health benefits. You get prolonged life, reduced disease risk — all of those things come in in the first 20 minutes of being active.” So really, you can relax and don’t have to be on the look-out for the next killer work-out. All you have to do is get some focused 20 minutes in to get the full happiness boost every day.