Sport and memory, a very good couple

As we delve deeper into our knowledge of the brain, science continues to agree with the motto mens sana in corpore sano (“healthy mind in a healthy body”). It is more than proven, for example, that staying physically active makes it more difficult for cognitive decline, which is inherent to aging. But it is also an effective memory enhancer at any age and with immediate results.

This is how we archive memories
If we are going to talk about memory and exercise, let's first define some important elements of the former. As we all know, memory is the ability by which we store memories that we can later recover. In the nervous system, it is basically built through three phases.

Firstly, an external or internal perception of the organism is encoded in the biochemical language of our brain. This fundamental process determines what we learn from the environment. The better the information is encoded, the more likely it is to last.

Once the new memory is encoded, it can become permanent or disappear. To be durable, the second phase of memory, consolidation, is required, although this stage is not the focus of this article. Finally, the third phase has to do with our ability to recover the file, and is also not relevant to the topic at hand, beyond understanding the process.

Today we know, thanks to studies in neuroscience, that the coding mechanism requires a set of biological responses and that there are certain fundamental proteins for it to occur. In particular, what is known as brain-derived neurotrophic factor (BDNF) stands out. In its absence, we cannot generate new memories.

BDNF is so important that, if its concentration is increased in specific regions of the brain, it can enhance learning processes.

The key is in the lactate
And it is at this moment when we square the circle. In 2019, researcher Lauretta El Hayek found that experimental animals memorized better when they exercised. This improvement was obtained as a consequence of the release of lactate, a waste product of anaerobic metabolism produced by physical activity that we currently know is very useful in various tissues.

In particular, lactate has the ability to cross the blood-brain barrier (whose function is to prevent all substances circulating in the blood from reaching the nervous system) and reach the brain. Once here, it is taken up by neurons and stimulates the production of BDNF.

In this way, the lactate generated by physical exercise increases BDNF levels in determining regions of the brain and enhances learning.

An experiment with young university students
These results in mice invited us to replicate the research with people. The good thing about humans is that we have the ability to produce a lot of lactate with exercise if it is very intense.

Today we already know that physical activity can acutely affect cognitive responses. Therefore, the interesting thing was to compare high-intensity physical exercise (with a lot of lactate production) with gentle activity (with hardly any lactate). To carry it out, our research team selected young university students, who in principle are at their maximum learning potential and are capable of generating very intense efforts. Consequently, they can produce a lot of lactate.

After exercising, and after between 15 and 20 minutes of rest, the volunteers had to carry out a memorization task. This way we would check how it affected the coding phase. And the conclusion was that, once again, humans are not that different from mice.

When participants performed high-intensity exercise they were able to remember both words and images better. Additionally, there is a correlation between the amount of lactate released and improvement in memory. This relationship does not seem to be strictly linear, but possibly works in steps, something very typical in our biological responses to physical exercise.

In any case, an intense (but not fatiguing) session of exercise prior to a learning task enhances our encoding capacity.

There are still many questions in the air that we must resolve to turn this process into a useful tool for teaching, but without a doubt we are facing an innovative element in the field of learning.

Read the article on the original website, clicking on the button below this text.

Source: The Conversation. Authorship:

Diego Pastor Campos
Professor in Sports Sciences, Miguel Hernández University