Dementia and sedentary life: how it affects inactivity

Dementia and sedentary life: how it affects inactivity

Dementia and sedentary life are two concepts that many people still do not know that go hand in hand to a greater extent than it seems. We usually associate only inactivity to cardiovascular diseases, to gain weight, to lose flexibility ... However, physical inactivity, thanks to advances in science, has found that the relationship between the appearance of dementia and sedentary life can be closer what it seems like.

Throughout the article the concept of dementia and sedentary life will be addressed. As well as the benefits of physical exercise and, above all, the role of neurogenesis in the role of dementia prevention. In this way, the importance of physical activity for proper brain functioning will be investigated and the negative consequences of sedentary lifestyle will be manifested.

Dementia and sedentary life


According to the American Psychiatric Association (APA), dementia is defined as a "disorder characterized by an acquired cognitive impairment of sufficient severity to affect social and / or professional functioning". When talking about dementia, one must distinguish between two concepts. As described by the Menéndez-González team (2013):

  1. On the one hand, we find the Age-Associated Cognitive Deterioration (DECAE). In this type of deterioration,"The neuropsychological test score is close to the average of subjects of the same age and educational level."
  2. On the other hand, we have Slight Cognitive Deterioration (DCL). It means "to cognitive disorders that, without meeting dementia criteria or significantly affecting functional capacity, they represent a deterioration with respect to the expected age, and identifies a group of people at risk of developing dementia in the future".
Thus, the difference between one and the other is that the first (DECAE) is the deterioration that is associated with the passing of the years. While the second (DCL) is an unexpected deterioration at the chronological age of the subject. Differentiating between these two types of impairments is important to get an idea about the influencing factors. For example, it is not the same to begin to suffer from a certain level of dementia with 90 years than with 60. In this case, some environmental factors might be influencing, that is, modifiable.

Sedentary life and benefits of physical activity

What is to lead a sedentary life? Basically in spend the day sitting without doing any specific physical activity. The factors can be several, among which stand out, long working hours, too many daily occupations or simply lack of appetite for exercise. While it is true that a large number of subjects lack time to practice a little sport, the same simply shows their laziness towards him.

"Life is not what you live but how you remember it and how you remember it to tell it."

-Gabriel Garcia Marquez-

That said, in the case of Mild Cognitive Impairment, different studies conclude that leading a sedentary life could influence the development of early dementia. As highlighted by the Menéndez-González team, physical activity benefits cognitive health through:
  • Benefits in the cardiovascular system and cerebrovascular system.
  • Increase in neurogenesis.
  • Improvement of cerebral cytoarchitecture (blood vessels, dendrites and microglia).
  • Neural plasticity and electrophysiological properties.
  • Increase in brain growth factors.
  • Decreased formation of amyloid plaques of Alzheimer's disease.
Neurogenesis, why is it so important?


The research team of Peter S. Eriksson, in 1998, demonstrated in humans that we produce new cells during adulthood. That is why it is so important to encourage its creation to prevent and / or slow dementias. The creation of new cells is a dense and complex process, so in this section we will discuss the concept of neurogenesis and the role of physical activity. So, little by little, the role of a sedentary life will be related to this very important process. Neurogenesis, given its great importance, deserves its own section in this article that deals with the relationship between sendental life and dementia. Why is this concept so important? Until relatively few years ago, neurons were thought to stop occurring at a certain age. However, thanks to the investigation it was found that the brain generates new cells throughout its adult life. This generation of new cells is what known as neurogenesis.

How to promote neurogenesis: the role of physical activity

As the Arias-Carrión team (2007) states, "it is known that physical activity, enriched environmental, energy restriction and modulation of neuronal activity, among other factors, they act as positive regulators of neurogenesis". That said, the authors highlight another important aspect. First we will quote his words and then they will crumble for a better understanding.
"Memory is the newspaper we carry with us everywhere." -Oscar Wilde-
The Arias-Carrión team maintains that "alterations in the hypothalamic-pituitary-adrenal axis, induced by persistent stress situations during development, decrease the generation of new cells in the dentate gyrus. Thus, It is known that the cellular proliferation of the dentate gyrus decreases due to the effect of glucocorticoids, which are released in response to stress.". The conclusion of these words is that through stress we release glucocorticoids, better known as cortisol, the famous stress hormone. The appearance of cortisol in the body decreases the generation of new cells, that is, blocks neurogenesis. Now, how can we cope? Exact!

Benefits of physical exercise

Physical exercise reduces cortisol levels and therefore increases the production of new cells. Therefore, a sedentary life, in which the body does not participate in any type of physical activity is more prone to not eliminate cortisol, thus preventing the generation of new cells and being able to "advance" the onset of dementias. On the other hand, the team of Olivares Hernández (2015), states that "The relationship between hippocampal neurogenesis and learning and memory is evident, the new neurons generated in the hippocampus provide the anatomical substrate that processes and encodes the new information acquired". Thus, this research shows the relationship between neurogenesis, learning and memory. That is, it highlights that encouraging the process of creating new neurons can prevent and / or delay the manifestation of dementias.


Arias-Carrión, O., Olivares-Bañuelos, T. and Drucker-Colín, R. (2007) Neurogenesis in the adult brain. Journal of neurology, 44 (9), 541-550. Menéndez, M., Martínez, M., Fernández, B. and López-Muñiz, A. (2011). Lifestyle and risk of suffering from dementia. Medical Records, 7 (31), 1-7. Olivares, J., Juárez, E. and García, F. (2015). The hippocampus: neurogenesis and learning. Medical Journal of the Veracruzana University, 20-28.