Treadmill walking alters stride time dynamics in Parkinson's disease

Area of Science:

• Biomechanics of human locomotion
• Neurorehabilitation strategies
• Complex systems analysis of gait dynamics

Background:

• Treadmill training is explored for improving gait rhythmicity in Parkinson's disease (PD).
• Treadmills can constrain stride-time fluctuations in healthy adults, mimicking pathological gait.
• The effect of treadmills on dynamic gait properties in PD remains unclear.

Purpose of the Study:

• To investigate differences in stride time fractal dynamics between treadmill and overground walking in individuals with Parkinson's disease.
• To compare these dynamics between Parkinson's disease patients and healthy controls.

Main Methods:

• 15 individuals with Parkinson's disease and 15 healthy adults walked overground and on a treadmill.
• Inertial measurement units captured gait speed, stride times, and stride time variability.
• Adaptive fractal analysis computed fractal exponents (α) for stride time fluctuations.

Main Results:

• Gait speed decreased and stride times increased on the treadmill for all participants.
• Stride time variability was higher in the Parkinson's disease group compared to controls.
• Stride time fractal exponents (α) were significantly higher during treadmill walking (mean α = .910) versus overground (mean α = .797) in individuals with Parkinson's disease, but not in controls.

Conclusions:

• Treadmill walking in Parkinson's disease leads to increased stride time fractal scaling, approaching a 1/f signal (α = 1.0).
• This suggests treadmills may promote optimal structural variability for gait in PD.
• Treadmill training could offer a more effective approach to improving walking dynamics in Parkinson's disease than overground training.