Next time you're contemplating skipping a workout to finish a project in the office, consider this new finding from a German study: Physical fitness is associated with better brain functioning in young adults.
Researchers have long understood that exercise improves people's cognitive performance, including their executive functioning, attention and memory, as well as their brain structure. In older adults especially, physical activity has been shown to increase the size of the hippocampus, which is the part of the brain responsible for memory, learning and emotion.
But Jonathan Repple, M.D., lead study author, and his colleagues were curious if this connection could be found in young adults as well. They also wanted to see whether it was indeed physical fitness, rather than other factors such as body weight or education status, that was associated with better brain health, he tells CNBC Make It.
For the study, the researchers examined more than 1,200 MRI brain scans of people with an average age of about 29, which came from a voluntary survey called the Human Connectome Project. The volunteers who were surveyed completed a two-minute walking test that was designed to measure their endurance, then took a cognitive test. Researchers found that high levels of endurance were positively associated with higher scores on the exam.
Dr. Repple was surprised to find that there were visible differences between the brains of "fitter" and "less fit" people, and they translated to brain health and better cognitive performance, Dr. Repple says. Specifically, those who performed better on the walking test also had more white matter in their brain. White brain matter is important because it contains nerve fibers that allow signals to travel faster and more efficiently, plus protects those nerve fibers from injury, according to Medline Plus.
The takeaway? Working on improving your fitness skills could improve your cognitive ability, which includes your memory and problem-solving skills.
This was just a cross-sectional study, meaning researchers just "observed" the association, and they can't say exactly how much or what kind of exercise would result in these specific brain benefits. Generally, it's recommended people get 150 minutes a week of moderate intensity activity — a brisk walk, biking or even doing housework would count —according to Department of Health and Human Services.
Next, Dr. Repple says they'd like to experiment with people who have depression, schizophrenia or bipolar disorder to see whether exercise would result in similar improvements. "However, a lot points towards this idea already," he says.
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