[Via New York Times] A recent publication from The Journal of Comparative Neurology indicates that being inactive may change brain function, just as much as being active does. The study from the Neurology Department of Wayne State University School of Medicine found that being sedentary (often caused by laziness) changes the shape of certain neurons in ways that significantly affect not just the brain, but also the heart and circulatory system[.]
The research studied two groups of rats: one in cages with running wheels, and the others confined without any means of exercise. The results showed normal neuron brain development for the active rats, and abnormal neuron brain developments of vessels and pathways for the sedentary rats.
Inactivity affects a part of the brain called the rostral ventrolateral medulla which primarily controls the sympathetic nervous system. This part of the brain is largely responsible for controlling breathing, blood pressure, and blood vessel constriction.
The study posits that when a mammal (human or nonhuman animal) is inactive (lazy), the sympathetic nervous system will constrict blood vessels erratically and unregularly which can lead to high blood pressure and other very serious cardiovascular problems. The creation of excessive tentacle-like neurological branches for neurons to travel makes them more sensitive to stimuli, thus increasing blood pressure and promoting conditions such as heart disease.
In its conclusion, the study suggests that at a cellular level, within the brain and throughout the body, the amount that we remain active on a regular basis can have direct and indirect influences on our overall health.