Adaptive treadmill control can be manipulated to increase propulsive impulse while maintaining walking speed

Area of Science:

• Biomedical Engineering
• Rehabilitation Science
• Motor Control

Background:

• Propulsion is crucial for effective gait, but often impaired after stroke.
• Adaptive treadmills (ATM) offer potential for gait rehabilitation by modulating training parameters.
• Novel ATM controllers can adjust belt speed based on real-time gait dynamics.

Purpose of the Study:

• To investigate the effect of increased propulsive feedback gain on propulsion measures and walking speed.
• To modify an ATM controller to prioritize propulsion feedback relative to step length.
• To assess the efficacy of modified ATM for enhancing propulsive impulse in gait training.

Main Methods:

• Twenty-two participants completed five trials on a novel ATM with varying controller gains.
• The controller's relative importance of propulsion to step length was systematically modified.
• Walking speed, peak and impulse ground reaction forces (AGRF, PGRF) were measured and analyzed.

Main Results:

• Walking speed and peak propulsive forces remained consistent across conditions.
• Anterior Ground Reaction Force (AGRF) impulse significantly increased with higher propulsive feedback gain.
• Posterior Ground Reaction Force (PGRF) and net impulse showed no significant differences between conditions.

Conclusions:

• Modifying ATM controller gain can effectively increase propulsive impulse without altering walking speed.
• This ATM modification shows promise for enhancing gait rehabilitation in individuals with impaired propulsion.
• The ATM can be tailored to provide controlled resistance, promoting greater propulsive effort during training.