Study Finds 5 Subtle Walking Changes That Show Up Before a Parkinson's Diagnosis

By the time most people are diagnosed with Parkinson’s disease (PD), the condition has most likely been developing quietly, undetected, for years. This early period — before the typical tremors, stiffness and slowness that lead to a diagnosis become obvious — is known as the prodromal phase. Finding ways to detect Parkinson’s during this window is a major goal of research, because earlier identification could improve outcomes through earlier treatment and better care. 

Researchers are working to find biomarkers that could detect PD early. In addition to lab tests, wearable technology may monitor daily activity and detect subtle clues of disease. These “digital gait biomarkers,” may provide a simple, accessible way to detect early signs of Parkinson’s.  

A new study published in the Journal of Neural Transmission suggests that subtle changes in how people walk in everyday life may be detectable up to nearly seven years before a Parkinson’s diagnosis — and that an ordinary wrist-worn device, similar to a fitness tracker, may be able to detect those changes. 

Study Results

Researchers at the University of New South Wales in Australia analyzed data from more than 73,000 participants in the UK Biobank, a large long-term health study. Between 2013 and 2015, each participant wore a wrist accelerometer (a motion sensor) for seven days, and was then followed for up to 10 years through their medical records. During that time, 314 people were diagnosed with Parkinson’s.

The researchers used software called Watch Walk to translate raw motion data into 17 detailed measures of walking — not just step counting, but the quality and structure of movement: walking speed, step rhythm, how long they walked continuously and how their hands and arms moved.

Researchers then compared people later diagnosed with Parkinson’s with those who were not. People who developed Parkinson's had five measures that stood out consistently years before diagnosis. They:

1. Took fewer daily steps. They took substantially fewer steps per day, and the gap grew wider as their diagnosis approached.
2. Had slower top walking speed. Their fastest walking pace was slower, suggesting a reduced ability to speed up when needed.
3. Had reduced arm movement. They spent more time walking with their arms held still — for example, hands held in front of the body — and less time with a natural arm swing. Reduced arm swing is an early sign of Parkinson’s.
4. Showed changes in step rhythm. Their step patterns were, somewhat unexpectedly, more uniform — which the researchers suggest may reflect a loss of natural flexibility in how healthy people adjust their walking.
5. Displayed differences in walking patterns. The way their walking was broken up over the day — into shorter versus longer continuous stretches — also differed from those who did not develop Parkinson’s.

Of these, changes in arm movement were detectable the earliest — up to 6.8 years before diagnosis. The drop in daily steps was especially pronounced in the years closest to diagnosis.

Why is This Study Important?

Parkinson’s affects the brain circuits that control movement, so in practice, walking — a complex, coordinated activity — would show early signs of change. Postural instability, or difficulty balancing is one of the most challenging PD movement symptoms. Importantly, the technology from wearable sensors can break down the complex aspects of walking into components that can be analyzed separately.

What makes this study notable is that these changes were measured in the real world, during participants’ normal daily lives, rather than in a clinic. Continuous, at-home monitoring can capture patterns that a brief walking test in a doctor’s office might miss. It can also help identify potential problems years before someone is aware they exist.

The researchers also emphasize that the device used was a simple wrist-worn sensor, the kind that could be built into widely available consumer wearables, like a smartwatch. That makes this approach potentially scalable to large numbers of people. 

What Does This Mean for People with Parkinson’s?

This study does not mean that a smartwatch can diagnose Parkinson’s. The walking differences the researchers identified are subtle and show patterns across large groups — not a test that could predict whether someone will develop Parkinson’s. But these findings bring us closer to a future where observational, easy-to-record changes in the way we walk could help identify Parkinson’s years before a diagnosis. 

That possibility is significant. Growing evidence suggests that Parkinson’s leaves detectable traces years before diagnosis and traditional symptoms appear. As potential disease-slowing therapies move through clinical trials, tools that can flag people in the earliest stages could become increasingly valuable — helping researchers identify candidates for prevention studies and, eventually, helping doctors intervene sooner.

Learn More

The Parkinson’s Foundation believes in empowering the Parkinson’s community through education. Learn more about PD and movement through our resources below, or by calling our free Helpline at 1-800-4PD-INFO (1-800-473-4636) for answers to your Parkinson’s questions.

• 10 Early Signs
• Trouble Moving or Walking
• Finding Balance: Steps to Move Safely and Minimize Falls with Parkinson’s