There are several possibilities for why exercise is beneficial for the brain. Examples are as follows:
--increasing the blood and oxygen flow to the brain
--increasing growth factors that help create new nerve cells[35] and promote synaptic plasticity[36]
--increasing chemicals in the brain that help cognition, such as dopamine, glutamate, norepinephrine, and serotonin[37]
Physical activity is thought to have other beneficial effects related to cognition as it increases levels of nerve growth factors, which support the survival and growth of a number of neuronal cells.[38]