Source: http://www.businessinsider.com/aerobic-exercise-workout-body-brain-benefits-gut-microbes-2017-12
Aerobic exercise, or cardio, might be the closest thing we have to a miracle drug.
When we commit to regular workouts that raise our heart rate and get us moving and sweating for a sustained period, magical things happen to our mind and body. We start to think more clearly, feel better about ourselves, and even build buffers against age-related cognitive decline. Our lungs and heart get stronger, too.
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Aerobic exercise “has a unique capacity to exhilarate and relax, to provide stimulation and calm, to counter depression and dissipate stress,” according to an article in the Harvard Medical School blog “Mind and Mood.”
Some benefits of cardio, like a lift in mood, can emerge as soon as a few minutes into a sweaty bike ride. Others, like improved memory, might take several weeks to crop up.
The reason aerobic workouts seem to lift our spirits seems related to its ability to reduce levels of natural stress hormones, such as adrenaline and cortisol, a recent study in the Journal of Physical Therapy Science found. Activities like running and swimming also increase overall blood flow and provide our minds fresh energy and oxygen — another factor that could help us feel better.