From a physiological point of view, exercise is good for cardiovascular and respiratory health. What about the effects of exercise on your mental health? What happens to the brain when you move?
Exercise has numerous psychological, physical and social benefits. In addition to improving your immune system and preventing certain diseases, it can also improve your mood, self-esteem and physical appearance.
Exercise regulates the secretion of neurotransmitters, which are chemical cells responsible for communication between neurons.
It also plays a role in neurogenesis, a process by which the body regenerates neurons and creates new neurons. All of this contributes to a healthy brain and good cognitive function. We will now take a closer look at what those processes are.
Neural growth in the brain when you move
A common belief is that aging and certain habits lead to neural death. However, in recent years, science has shown that this is not the case.
Researchers have seen how neurons can repair themselves, find compensatory mechanisms and increase the effectiveness of the networks they form. This ability is called neuroplasticity and is critical for development, learning and recovery after injury.
In the context of changes in the brain when you move, one mechanism of neuroplasticity is neurogenesis. The production of new neurons is not a process that takes place all over the brain. The hippocampus, the olfactory bulb, and the subventricular zone of the lateral ventricle are the areas in the brain where this phenomenon occurs.
In the last decade, researchers have endeavored to determine which factors encourage and which inhibit neurogenesis. Two factors they have identified so far are an enriched environment and exercise.
How does it happen?
Scientists don’t yet know exactly how exercise affects neurogenesis. However, they do have sufficient evidence to conclude that exercise increases brain-derived neurotrophic factor (BDNF ) and vascular endothelial growth factor (VEGF) levels in the body.
BDNF and VEGF are proteins that promote neural survival and blood vessel formation, respectively.
Researchers have found that BDNF levels in your brain double or even triple when you exercise, and then drop back to normal levels about an hour later.
Scientists associate the increase in the protein with a 2% annual increase in the volume of the hippocampus. During the normal aging process, the hippocampus decreases by 1-2%.
In summary, exercise increases the expression of the NMDA receptor on the neurons of the hippocampus. Activation of these receptors increases calcium levels in the synopsis, activating pathways that ultimately regulate the expression of BDNF proteins.
BDNF then activates another receptor (TrkB) present in the parental cells in the hippocampus, promoting the production of new neurons.
While the mechanism linking VEGF to neurogenesis is not yet clear, researchers believe it plays a direct and indirect role.
- On the one hand, it induces changes in the neural mother cells.
- On the other hand, it increases the number and circumference of the blood vessels.
An increase in the number and circumference of the blood vessels improves circulation and therefore the health of the cells.
Researchers have determined that exercise and the resulting increase in VEGF leads to an increase in maternal cells and a decrease in cell death, modulating the expression of macrophages (cells of the immune system that eliminate foreign substances).
Exercise also leads to an increase in a number of neurotransmitters. For example, when you exercise, your body produces more catecholamines. These are neurohormones that prepare your body to respond to stressful, threatening or physically active situations.
Other neurotransmitters in this group include:
The increase in these substances and the increase in endorphins is therefore the reason why exercise improves your well-being.
Another consequence of exercise is a drop in cortisol, the so-called stress hormone. This also reduces the harmful effect that cortisol has on your body.
Learning and cognitive function
The process of neurogenesis, and neuroprotection in general, mainly takes place in the hippocampus. This area of the brain specializes in spatial learning and the consolidation of long- and short-term memory.
Thus, in the context of the effect of exercise on the brain, several studies indicate that regular exercise improves learning and memory.
As if that were not enough, this effect also appears to extend to other cognitive abilities through its positive effect on mood and stress reduction.
Processing speed, decision making and selective attention can all be improved through exercise. So it appears that exercise is linked to an improvement in overall cognitive performance.