MONTREAL — The beneficial effects of moderate physical activity on cognition are greater than those of vigorous physical activity, researchers at the University of Ottawa have found.
This study would also be the first to demonstrate the effects of physical activity on cognitive health using a genetic approach.
Professor Matthieu P. Boisgontier and his colleagues have measured that the cognitive benefits of moderate physical activity are 50% greater than those of sustained physical activity.
“We showed that there is a relationship between moderate-intensity physical activity and vigorous-intensity physical activity that would explain the level of cognition, the level of cognitive reasoning ability, and that’s independent of age,” said Boisgontier, who is an associate professor of rehabilitation science from the Faculty of Health Sciences at the University of Ottawa and a Principal Investigator at the Bruyère Research Institute.
“We had a population of 8 to 96 years old, and regardless of gender, male or female, it works.”
The researchers used a technique called Mendelian randomization with latent genetic confounders, which analyzes the tiny genetic differences that exist between individuals.
These differences, Professor Boisgontier said, may explain why some are more likely than others to be physically active, along with factors such as environment, education and socioeconomic status, among other things.
The results again underscore that physical activity of any intensity has a positive effect on brain health and on factors such as memory, problem solving and concentration, and reaction time, the researchers said in a press release.
These findings, the researchers say, join those of previous studies that had shown the effect of exercise on the release of a protein, BDNF, that promotes the formation of new neurons, new connections between those neurons, and new blood vessels that feed those neurons .
This effect would explain the mechanisms underlying the benefits of physical activity on cognitive function.
Never late
All physical activity stimulates the brain’s production of the BDNF protein, Boisgontier said, so the data is a reminder that it’s never too late to get physically active and reap the benefits.
“We understand that no matter when we start life, we will have the benefits, because even if I’ve been exercising all my life and you start now, the release of these proteins in you will be the same as in me, he explained. So that’s really something from my perspective that’s pretty powerful and shows that regardless of when you start, it has positive effects on cognition.”
The results of the study also showed that the positive effect of moderate physical activity on cognition is 1.5 times greater than that of vigorous physical activity, continues Mr. Boisgontier, which is consistent with what has already been found in the scientific literature.
The psychological aspect of physical activity may come into play, he explained: Intense activity inevitably requires more effort and can even be more painful, which reduces the pleasure some get from it and can undermine their motivation to repeat the experience.
“We must continue to spread this public health message that physical activity is good for physical health, but also for mental health and cognition, throughout life,” concluded Mr. Boisgontier.
Around 350,000 people took part in this project, which is an international collaboration between Canada; the Swiss universities of Geneva, Lausanne and Fribourg; the American Universities of Arizona and Southern California; and Massachusetts General Hospital.
The results of this study were published in the highly influential journal Nature.