There are a couple of health problems that everyone dreads. A diagnosis of cancer is most unwelcome. Neurological conditions run a close second, though. If a doctor diagnoses Parkinson’s disease or ALS (aka Lou Gehrig’s disease), the patient has a right to be frightened. Equally devastating is a diagnosis of dementia. Can exercise improve cognitive function and perhaps delay the onset of dementia? In other words, might exercise save your brain? A few studies suggest the answer could be yes.
Review Links Ongoing Physical Activity to Better Cognitive Function:
Several studies suggest that older people who want to ward off cognitive decline in their later years need to keep moving (JAMA Network Open, Feb.1, 2024). An analysis of 104 controlled trials confirms that continued physical activity can help prevent cognitive impairment, although the effect is modest. More than 300,000 people participated in these studies, which showed improved global cognition, episodic memory and verbal fluency in active individuals. Most of these studies were of moderate or low quality, however. Higher quality physical activity measurements and higher follow-up rates were linked to better results on cognitive tests. For this outcome, more is better, at least up to about 16 hours of exercise a week. Nonetheless, you don’t need to be a professional athlete to have exercise save your brain.
Aerobic and Resistance Exercise Combined with Computer Training Improve Cognition:
A randomized controlled trial compared combined vigorous aerobic and resistance training to gentle balance exercises (JAMA Network Open, July 20, 2023). In addition, the 175 participants, all with mild cognitive impairment, did computerized cognitive training or sham training on the computer. These volunteers, between 65 and 84, also took either vitamin D or placebo pills. The interventions lasted for five months, and volunteers took standardized tests at six months. In addition, three-fourths of the participants showed up for the assessment after one year.
The group doing exercise plus computerized training performed significantly better on cognitive test scores after six months. The authors note that the average improvement on the cognitive test, called ADAS-Cog-13, was 2.64 points. This is higher than results from most pharmaceutical trials conducted in similar populations. Perhaps because they did not continue the exercise or the cognitive training, the participants did not show significant between-group differences after a year.
All in all, the investigators are quite optimistic about the potential for these interventions to help people. Please excuse the medical jargon below; we thought you’d like to see the entire summary.
The authors conclude:
“The SYNERGIC Trial demonstrated that a multidomain intervention of progressive aerobic-resistance exercises with sequential cognitive training can improve global cognition, including memory, attention, word recognition, and orientation in older adults with MCI, as measured by one of our primary outcomes, the ADAS-Cog-13. The multidomain intervention effect was larger than the improvement from exercise alone. Vitamin D supplementation had no significant benefit. Our findings suggest that this multidomain intervention could induce a clinically meaningful cognitive improvement in individuals with MCI, which may have important implications for their quality of life.”
Lace Up Your Sneakers to Have Exercise Save Your Brain:
SYNERGIC was not the first trial to suggest that exercise can benefit the brain as well as the muscles. In a study published in the journal Neurology (online Dec. 19, 2018), 160 volunteers with an average age of 65 tested the benefits of aerobic exercise, a DASH diet, a combination of the two, or health education sessions. The participants had cognitive impairments but no dementia when the study began. They completed cognitive tests to assess their executive function–the ability to plan, organize and make judgments.
Those who exercised for 45 minutes three times a week for six months made significant gains in tests of executive function. Adding the vegetable-rich DASH diet to the exercise helped even more. The improvement was the mental equivalent of dropping nine years from their age. That’s pretty impressive.
The volunteers assigned to health education sessions had worse scores on their executive function tests at the end of the six months than when they started. There are no drugs to ward off cognitive decline, but walking, jogging or cycling may be the best medicine for maintaining brain function as we age.
How Much Exercise Do You Need?
This is not the first research to demonstrate how you can use exercise to protect your brain. A study of three dozen healthy adults showed that even ten minutes of moderate physical activity can have measurable benefits for the brain (PNAS, Sept. 24, 2018).
Ten Minutes of Motion to Boost Your Brain:
The scientists used high-resolution functional magnetic resonance imaging to look at the volunteers’ brain activity before and after short exercise sessions. They found that after the workouts, the subjects’ brains had changed somewhat. They showed stronger connections between the hippocampal dentate gyrus and parts of the cerebral cortex that are important for processing memory. Consequently, the researchers are excited about this evidence that exercise improves the function of the hippocampus, which is a crucial area for memory.
Fit Kids Have Fit Brains:
Previous research has shown links between physical fitness and cognitive skills in young people. Moderate exercise even helps kids think better for several hours.
Another study showed a link between fitness and brain structure (Frontiers in Human Neuroscience, Aug. 19, 2014). Brain scans of 24 youngsters nine to ten years old showed that those who were more fit had more white matter integrity, hinting that their brains might have better connectivity. That could, in theory, help them with memory and learning.
The research didn’t actually show whether exercise boosts brainpower or being sedentary saps it. For that, investigators will have to conduct controlled trials of structured physical activity at recess and after school.
Remember Grandma’s admonition in the old days was “Go out and play!” It seems that far too few kids actually get that opportunity these days. This research suggests we should find ways to make it far easier for kids (and their parents and grandparents) to get aerobic exercise. Even a little bit can help.
