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Want to stay sharp? New study says exercise may be key

The researchers discovered that participants began experiencing cognitive improvements after working out for a total of 52 hours in approximately six months.Mario Tama/Getty Images/File 2002

Aging, sedentary adults who are worried about staying sharp might take pills or latch on to elaborate diets. But researchers at Harvard Medical School say they might be better off just getting out for a walk.

In a new study, Harvard researchers at Beth Israel Deaconess Medical Center found that nearly any type of exercise — walking, cycling, resistance training, yoga, weightlifting, etc. — can improve cognitive and thinking skills. More than 11,000 adults in their 70s participated in the review, which was published last week in the journal Neurology Clinical Practice.

Lead author Joyce Gomes-Osman, a postdoctoral research scholar at Beth Israel, said “there is solid evidence to suggest that maintaining a regular exercise regimen can improve brain health” and she hopes the study will convince people it’s not too hard to get started on an exercise plan.


The researchers also discovered that participants began experiencing cognitive improvements after working out for a total of 52 hours in approximately six months.

“Each of these sessions gives you points that you rack up, and when we get to about 52 hours, then . . . we have this opportunity to reap the benefits of the exercise,” Gomes-Osman said in a telephone interview, though she added that the number of hours before a person sees improvement could differ from person to person.

She said the benefits accumulate over the long term. Shorter, more intense, exercise sessions over the short term don’t count as much as a steady exercise routine over a longer period.

“You can think of it as exercise turning back the clock of age in your brain,” she said.

“We live in an era of instant gratification . . . but the encouraging thing about this is that it emphasizes the idea that you shouldn’t be discouraged if you don’t feel something in the first month,” Gomes-Osman said. “You just have to keep going.”


Staying mentally alert while aging is becoming an increasingly important topic, she said.

“We need to discuss this as a society because the global population is aging. By 2035, the scale is going to tip, and older adults will be more plentiful than younger adults,” she said, defining “older adults” as age 65 and up.

Scientists have found that as we age, our central nervous system slows the production of new cells in our brain’s hippocampus, which affects thinking and problem solving. But researchers say regular endurance exercise can stimulate the production of a protein — called the brain-derived neurotrophic factor, according to a 2016 Harvard Medical School study.

Over time, that protein “helps new neurons survive and thrive,” Gomes-Osman said.

“Sometimes it’s hard to translate these studies to people’s lives,” she said, “but I think we took a real important step in creating advice to translate results of evidence of exercise and brain health to a practical application that’s applicable to everybody.”

Elise Takahama can be reached at elise.takahama@globe.com. Follow her on Twitter @elisetakahama.