Sports reduce the risk of Parkinson's disease in everyone, regardless of exercise frequency

Previous studies have confirmed that the duration of physical exercise has a direct impact on Parkinson's disease (PD); however, the relationship between different types of exercise and the risk of developing PD remains unclear. A recent study published in npj Digital Medicine used data from the UK Biobank to examine the relationship between the risk of developing PD and different exercise regimens.

How does exercise affect the risk of Parkinson's disease?

Parkinson's disease is a neurodegenerative disorder characterized by postural instability, slow movements, muscle tone, and resting tremor. The development of PD can be influenced by factors such as the environment, genetic predisposition, and lifestyle, including daily exercise.

PD primarily affects people aged 50 years and older. Researchers predict that by 2030, the number of people suffering from PD will reach 8.7-9.3 million worldwide. Thus, given the growing burden of PD, it is of utmost importance to identify risk factors at an early stage and develop preventive measures.

There is growing evidence that exercise has significant benefits for people with PD. The World Health Organization recommends at least 150 minutes of moderate-to-vigorous intensity physical activity (MVPA) per week.

Studies have shown similar effectiveness of two specific exercise regimens in reducing the risk of cardiovascular disease and depression. However, the role of specific exercise regimens in reducing the risk of PD has not been studied.

About the study

The researchers examined the relationship between different exercise regimens and the incidence of PD. Data were collected at 22 sites in Wales, Scotland and England using physical and functional assessments, interviews, questionnaires and biological procedures.

The initial sample included 502,389 individuals from the UK Biobank. We excluded 402,282 individuals with incomplete exercise data and 1,000 individuals with pre-existing PD. An additional 10,607 participants were excluded due to missing covariate data, resulting in a final sample of 89,400 individuals.

Participants were divided into "inactive" and "active" groups. The "active" group was further subdivided into "weekend warriors" (WW), who exercised one to two days a week, and "regularly active" who exercised throughout the week.

A wrist-mounted triaxial accelerometer, Axivity AX3, was used to obtain exercise data. A multivariate Cox model was used to determine the relationship between different exercise modes and the risk of developing PD.

Research results

During a mean follow-up of 12.32 years, PD developed in 329 individuals. Both WW and regular exercise were significantly associated with a reduced risk of developing PD.

The onset of PD was equally well prevented by both the uniformly distributed exercise time and the WW regimen. This observation suggests that exercise duration may have a greater impact on reducing the risk of PD than exercise frequency.

Subgroup analyses were performed for five covariates, including alcohol consumption status, gender, family history, diabetes, and blood pressure. No significant associations were found between exercise and these factors.

Previously, one study reported that higher levels of exercise may reduce the risk of PD in men but not in women. In contrast, another study conducted in the US documented a positive effect of exercise on the risk of PD in both men and women. Current research has also shown a similarly reduced risk of PD in physically active men and women compared to inactive ones.

Restrictions

A key limitation of this study is that UK Biobank only recorded exercise data for one week for each participant. As multiple measurements were not taken, it is possible that participants’ behaviour patterns changed during the week of observation and this may not reflect their actual activity patterns, known as the Hawthorne effect.

Another limitation is the use of the Axivity AX3 device, which may not accurately record exercise data for certain activities, resulting in measurement errors.

The UK Biobank cohort is predominantly white, with other racial groups being in the minority, which may limit the general applicability of the findings. Further research in more diverse populations is therefore needed to confirm these observations.

Analyses of the consistency of wrist-accelerometer-derived motion data with those obtained by other methods are also needed. The small number of PD cases in the current study may have affected subgroup analyses for certain covariates, such as ethnicity.