Parkinson's disease patients who clock up four to eight hours of physical activity each week may experience slower declines in memory, thinking and movement, according to a study led by the University of Cincinnati. The research, published in Neurology, the official medical journal of the American Academy of Neurology, followed 294 people with mild-to-moderate Parkinson's disease over several years.
Participants had an average age of 66 and reported their weekly activity through structured interviews covering moderate and vigorous exertion at work, at home and during recreation. Moderate activity included brisk walking, light swimming, doubles tennis and household tasks such as washing windows, vacuuming or mowing the lawn. Vigorous activity took in jogging, fast cycling, team sports, singles tennis, shovelling and carrying heavy loads.
The patients were sorted into three groups according to how much they exercised: up to four hours a week, four to eight hours, and more than eight hours. Researchers then tracked cognitive health for up to five years and motor function for up to seven years. Each additional hour of weekly physical activity was linked to slightly slower declines in memory, thinking and movement, even after accounting for age, sex, education, weight and disease severity.
Those who were active for four to eight hours a week showed slower declines in memory and thinking than those who exercised for less than four hours. Exercising for more than eight hours a week did not appear to deliver extra benefits for cognition, suggesting a ceiling effect rather than a case of more always being better.
«Parkinson's disease is a brain disorder that causes movement and cognitive problems that gradually worsen, leading to disability and a loss of independence,» said study author Dong-Woo Ryu, M.D., Ph.D., of the University of Cincinnati and The Catholic University of Korea. «Previous research has shown associations between physical activity and movement symptoms. Our study found physical activity may have dual benefits, with associations with slower declines in movement and cognition.»
Ryu noted that any potential advantage may depend on how long patients stay active and whether they keep exercising over time. «While our study found small differences between activity levels, these differences may become more meaningful over time,» he said.
The researchers acknowledged important limitations. Because the study was observational, it cannot establish whether exercise directly slows the progression of Parkinson's disease. Participants reported their own activity levels, so they may not have remembered accurately how much they exercised. All were drawn from a single location and were primarily White, which may limit how far the results can be generalised.
Dr Vibhash Sharma, a neurologist at UT Southwestern in Dallas, Texas, who specialises in Parkinson's disease and other movement disorders and was not involved in the research, said the findings reinforced the value of regular activity. «Exercise has well-established benefits for physical fitness and mobility, along with potential benefits for brain health through mechanisms that are not yet fully understood,» he told Fox News Digital. «These findings further emphasize the importance of regular physical activity in managing Parkinson's disease.»
Sharma described the multi-year follow-up, with assessments of both motor and cognitive function, as a strength of the work. He also raised the possibility that patients whose disease progresses more slowly from the outset may simply be more likely to remain physically active, a confounding factor that observational studies struggle to rule out.
The authors said most participants had relatively strong thinking and memory skills when the study began, so further research is needed to confirm the results. Randomised trials would be required to determine whether exercise directly slows cognitive or motor decline. The study was supported by a grant from the Gardner Family Foundation and the Precision Medicine in Neurodegenerative Diseases Fund.