For stroke survivors, exercise may offer a mental health boost

Stroke survivors who adhere to physical activity guidelines developed to ward off additional strokes may reap an added benefit: better mental health, new research suggests.

The study, published June 23 in the Journal of the American Heart Association, found stroke survivors who engaged in moderate physical activity at least four times a week experienced fewer days of poor mental health than their less-active peers. The study found similar mental health benefits for heart attack survivors.

"Physical activity in general among stroke survivors is essential," said senior study author Dr. Ramin Zand, a professor of vascular neurology in the department of neurology at Penn State College of Medicine in Hershey, Pennsylvania. "It's probably one of the most important things a person can do to reduce the risk of recurrent strokes. We know that mental health is related to physical health. The fact that they can also reduce the intensity of depression and anxiety with physical activity tells me that this is hitting two birds with one stone."

About 795,000 adults in the U.S. experience a stroke each year, placing them at risk for additional strokes. Up to one-third of them also experience post-stroke depression. Prior research has shown that physical activity can help prevent recurring strokes and reduce the symptoms of depression. But the frequency, intensity and duration of physical activity needed to improve mental health in stroke survivors had not yet been clearly defined.

The American Heart Association and American Stroke Association first issued physical activity guidelines for stroke survivors to help prevent secondary strokes in 2011. The guidelines were updated in 2014 and again in 2021.

The 2011 guidelines recommended at least 30 minutes of moderate-intensity activity up to three times each week. In 2014, the recommendation was updated to three to four 40-minute sessions of moderate or vigorous activity per week. And in 2021, the guidelines were scaled back to either 10 minutes of moderate activity four times each week or 20 minutes of vigorous activity twice a week.

"We wanted to see if the same group of guidelines would also improve mental health," said Dr. Ajith Vemuri, lead author of the new study and a staff scientist in the department of neurology at Penn State College of Medicine.

In the new study, researchers analyzed physical activity and mental health data for 36,854 stroke survivors who took part in the Behavioral Risk Factor Surveillance System, or BRFSS, an annual telephone survey of adults in the U.S. that asks questions about diseases, risk factors, self-care practices and health-related behaviors. The researchers matched self-reported physical activity from the BRFSS to guideline-recommended doses to determine adherence.

The analysis did not differentiate between types of strokes or take into account the differing physical capabilities of stroke survivors. It defined depression as having six days or more of self-reported poor mental health over the course of a month.

The findings showed stroke survivors who did not adhere to any of the physical activity guidelines approached the threshold for depression. But those who met the guidelines – regardless of which ones were used – did not.

"We found that adhering to any of these guidelines would improve mental health," Vemuri said.

However, for each of the different physical activity recommendations, benefits varied among subgroups. For example, adults 65 and older were most likely to lower their number of poor mental health days by following the 2021 guidelines, while younger adults achieved better mental health when they adhered to the 2011 and 2014 guidelines.

Overall, stroke survivors who adhered to the 2021 guidelines – the least rigorous of the three sets of guidelines – experienced nearly 6% fewer days of poor mental health than those who did not. Older adults, women and people with lower incomes experienced the greatest benefits.

Vemuri said older adults likely found it easier to adhere to the 2021 guidelines because they were less strenuous than the 2011 and 2014 guidelines.

Adhering to the more rigorous 2011 guidelines resulted in even greater differences in mental health. Overall, those who followed the guidelines experienced 11% fewer days of poor mental health than those who did not. Among this group, younger adults, Black stroke survivors and those who graduated from college or a technical school saw the greatest benefits.

Sticking with the 2014 guidelines – which were the most physically demanding – reaped the greatest mental health benefits. Overall, stroke survivors who adhered to these guidelines averaged nearly 15% fewer poor mental health days than those who were less physically active. Among this group, younger adults and Black stroke survivors benefited most.

On average, the biggest gains were achieved by engaging in 45 minutes of moderate-intensity physical activity at least four times a week.

Vemuri said the subgroup differences suggest that physical activity guidelines should be customized to groups to achieve the maximum mental health benefits.

The researchers also analyzed mental health benefits for people who survived heart attacks, using the 2011 guidelines. Heart attack survivors who adhered to these guidelines also experienced, on average, 13% fewer days of poor mental health than their peers who were less active.

Dr. Richard Harvey, a professor of physical medicine and rehabilitation at the Northwestern Feinberg School of Medicine in Chicago, said the results were not surprising, given the large body of research supporting the benefits of physical activity. Harvey was not involved in the new study.

"We know that in healthy adults, physical activity is beneficial for mental health," he said. "And we have some data that suggests that exercise in stroke patients is beneficial for mental health. This is a large dataset that supports that concept."

However, Harvey cautioned against reading too much into the differences among subgroups since other factors that weren't accounted for could be influencing the results. For example, younger adults who have strokes might have better neurological function and greater physical abilities than older adults, as well as more extensive social support.

"These factors can have an impact on one's overall mental health as well," he said.

Studies published in the American Heart Association's scientific journals are peer-reviewed. The statements and conclusions in each manuscript are solely those of the study authors and do not necessarily reflect the Association's policy or position. The Association makes no representation or guarantee as to their accuracy or reliability.