Want to boost your memory ? Daily exercise is the key

Now, new research sheds light on how running can improve learning and memory.

Running releases a protein that improves our memory, suggests a new study.

H.Y. Moon et al., "Running-induced systemic cathepsin B secretion is associated with memory function", Cell Metabolism, doi:10.1016/j.cmet.2016.05.025, 2016.

Other studies have suggested cathepsin B plays a role in the clearance of beta-amyloid plaques, which are known to contribute to the development of Alzheimer's disease and other neurodegenerative disorders.

Study senior author Doctor Henriette van Praag, a neuroscientist at the National Institute on Ageing in the United States, said: "We wanted to cast a wide net".

After exposing muscle cells in a dish to compounds that mimic exercise, researchers observed that the presence of cathepsin B production noticeably increased in the conditioned media of the cultures.

The researchers also found that people who exercised consistently for four months had increased levels of cathepsin B in their blood and better memory recall.

With these findings in mind, van Praag and colleagues set out to investigate how cathepsin B might impact memory recall in response to physical activity.

However, when both groups ran before their daily swim test, the normal mice were better able to recall the location of the platform, while the mice unable to make cathepsin B could not remember its location.

Every day for 1 week, both groups of mice engaged in a Morris water maze test, which required them to identify the location of a platform within a small pool.

After doing this task for a few days, normal mice eventually learned where to find the platform.

Researchers then compared memory recall in normal mice with that in mice lacking the ability to produce cathepsin B under both sedentary and running conditions.

Dr van Praag said the team the findings were important as it was the first time this had been tested. Also, after a run, protein levels increased in blood in mice, monkeys, and humans.

Looking forward, the researchers hope to understand how cathepsin B breaks the blood-brain barrier, the mechanism by which capillaries carry blood to the brain and spinal cord while obstructing the passage of foreign substances, as well as how it activates neuronal signaling, growth, and connections.

"Overall, the message is that a consistently healthy lifestyle pays off", van Praag says. "Exercise has so many health benefits, yet we know so little about many of these effects at a molecular level", said biologist David James of the University of Sydney who did not participate in the work. "The study supports that the more substantial changes occur with the maintenance of a long-term exercise regimen".