The findings suggest that regular physical activity may offer two important benefits for people living with Parkinson’s disease: slower cognitive decline and less worsening of motor symptoms. However, researchers emphasized that the study found an association between physical activity and delayed symptom progression. It did not prove that exercise directly slows the progression of Parkinson’s disease.

“Parkinson’s disease is a brain disorder that causes motor and cognitive problems that gradually worsen and lead to disability and loss of independence,” said study author Dong-Woo Ryu, MD, PhD, of the University of Cincinnati in Ohio. “Previous studies have shown an association between physical activity and motor symptoms. Our study shows that physical activity may have dual benefits, with an association between exercise and slowing cognitive decline.”

Seven-year study tracked exercise and Parkinson’s symptoms

The study included 294 adults with mild to moderate Parkinson’s disease. Participants had an average age of 66, and researchers monitored their health for up to seven years.

To assess activity levels, participants completed questionnaires estimating how much time they spent each week on physical activity at work, at home, and during hobbies and recreation.

Researchers classified activities by intensity. Moderate activities included brisk walking, doubles tennis, leisurely swimming, and household chores such as washing windows, vacuuming, and mowing the lawn. More demanding activities included running, fast cycling, team sports, singles tennis, shoveling snow, and carrying heavy objects.

The research team assessed physical activity in three ways. First, they calculated the total time participants spent in moderate or vigorous activity. They then combined duration and intensity to estimate overall activity, giving greater weight to more intense exercise. Finally, they separately measured time spent in strenuous activity.

Participants were divided into three groups based on total weekly activity time:

• Least active: Up to 4 hours per week
• Moderately active: 4 to 8 hours per week
• Most active: 8 or more hours per week

Each year, participants completed tests assessing the severity of their Parkinson’s symptoms, along with evaluations designed to track changes in thinking and memory.

More physical activity was associated with slower memory decline

One of the most notable differences involved cognitive performance. Researchers used a 30-point test of thinking and memory, with lower scores indicating poorer cognitive function.

Scores in the least active group decreased by an estimated average of 0.478 points each year. The moderately active group experienced a much smaller estimated annual decline of 0.090 points.

The estimated average annual decline among the most active participants was just 0.007 points, indicating that their cognitive scores changed very little over time.

Active participants also had less worsening of motor symptoms

Researchers also examined motor symptoms using a rating scale ranging from 0 to 132. Higher scores indicate more severe symptoms. Participants began the study with an average score of 23.

The least active group experienced a slight worsening in motor symptoms, with scores increasing by an estimated 0.143 points per year. In contrast, scores decreased by 0.225 points per year in the moderately active group and by 0.783 points per year in the most active group.

After accounting for participants’ age, gender, and how long they had been living with Parkinson’s disease, researchers found that the most active group had slower cognitive decline and less worsening of motor symptoms than the least active group.

The association was not limited to one type of exercise. Greater total active time, higher overall activity, and more time spent in vigorous exercise were each associated with slower declines in thinking ability and motor symptoms.

Why consistent exercise may matter in Parkinson’s disease

The results suggest that maintaining physical activity over long periods may be particularly important for people with Parkinson’s disease. Researchers noted that even small differences in annual decline can become more meaningful when they accumulate over several years.

“The benefits of physical activity for people with Parkinson’s disease may depend on how long they stay active and whether they continue to exercise over a long period of time,” Liu said. “Although our study found small differences between activity levels, these differences may become more meaningful over time. Participants generally had good thinking and memory skills at the beginning of the study, so our results should be interpreted with caution and further research is needed.”

Study limitations and what the findings mean

The researchers identified several limitations. Physical activity levels were based on participants’ self-reported estimates rather than direct measurements, so some activity levels may have been reported inaccurately.

The findings strengthen evidence linking physical activity with better long-term outcomes in Parkinson’s disease. However, additional research is needed to determine whether exercise itself can slow the progression of Parkinson’s symptoms.

Funding for the study came from grants provided by the Gardner Family Foundation and the Neurodegenerative Diseases Precision Medicine Fund.