Moderate physical activity practiced consistently and at all ages keeps overweight, type 2 diabetes, heart disease and even Alzheimer's at bay. In particular, those who regularly practice physical activity have a greater brain volume than those who are more sedentary. These benefits are also observed in the areas that are most commonly affected by Alzheimer's, thus ensuring a greater reserve of neurons. This emerges from a very recent scientific research published in the journal Neurology only a few weeks ago thanks to the work of a French team (Felisatti et al, Neurology, 2022).
The benefits of physical activity
Previous studies had been able to emphasize the benefits of physical activity, useful for keeping blood sugar under control and protecting the heart. Not only that, it was already known that exercise was able to protect brain cells from degenerative diseases. However, until now, there have been few studies dedicated to the subject and above all the mechanism of action with which physical activity has a neuroprotective effect had not been understood. Based on animal studies, the ability of physical activity to stimulate neurogenesis was hypothesized, while other research on humans had advanced the possibility that the beneficial effects of physical activity on the heart could then also affect brain health. To clarify this vital topic, especially for the purpose of developing a protective lifestyle against neurodegeneration such as Alzheimer's, the French researchers have developed the study we are talking about today.
Exercise protects the brain from neurodegeneration
Scientists have recruited 134 people, with an average age of 69 and healthy. Volunteers were subjected to questionnaires, in order to assess lifestyle and time devoted to physical activity, and to medical examinations, blood tests and magnetic resonances to assess the state of health of the body and brain. What emerged was that those who had remained more active all their life had, compared to those who were more sedentary, a greater volume of brain gray matter, even in areas of the brain normally more affected by Alzheimer's. What has been observed is further evidence that physical exercise protects against neurodegeneration, as already known. The extra contribution given by the study, on the other hand, was the explanation of how physical activity protects the brain. The researchers found two mechanisms, independent of each other. The first is that physical activity is beneficial for the heart, since those who were more active had lower insulin and body mass index values, which are considered indicators for evaluating cardiovascular risk. By protecting the heart, physical activity gives greater integrity to the brain structure. Moreover, this is understandable considering that, on the other hand, obesity and insulin dysfunctions lead not only to a greater cardiovascular risk, but also to an increased risk of neurodegeneration and Alzheimer's. Another noteworthy fact is that in those who practiced more physical activity, scientists also found an increase in brain glucose metabolism. Well, glucose metabolism in the brain is considered an important parameter for evaluating the state of health of the brain and the possibility that neurodegeneration may be developed. In fact, conditions of hypometabolism of glucose in the brain can indicate a possible development of Alzheimer's disease, even when the symptoms are not yet detectable.
Conclusions
A brisk walk, a swim or a bike ride, are activities that we should give ourselves often during the week, maybe even every day, but always in moderation and without exaggerating. From today we know, in fact, that a nice walk not only contrasts the pot belly and the overweight, heart diseases, sadness and diabetes but also neurodegeneration.
