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Updated: Jun 8, 2026
08:55
Determining and Controlling External Power Output During Regular Handrim Wheelchair Propulsion
Published on: February 5, 2020
Load on the upper extremity in manual wheelchair propulsion
H E Veeger1, L H van der Woude, R H Rozendal
1Department of Functional Anatomy, Faculty of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
Summary
This study modeled upper extremity contributions to manual wheelchair propulsion. Increasing mechanical advantage (MA) decreased mechanical efficiency (ME), with shoulder muscles identified as prime movers.
Area of Science:
- Biomechanics
- Human Movement Science
- Rehabilitation Engineering
Background:
- Manual wheelchair propulsion is a complex activity involving multiple upper extremity joints.
- Understanding joint contributions is crucial for improving wheelchair design and user training.
Purpose of the Study:
- To investigate the joint contributions during manual wheelchair propulsion.
- To analyze the effects of mechanical advantage (MA) on propulsion mechanics and efficiency.
Main Methods:
- Developed a three-dimensional upper extremity model.
- Applied the model to data from wheelchair ergometer tests with varying MA (0.58-0.87).
- Collected data on external power output (P(ext)), joint torques, and electromyographic (EMG) activity.
Main Results:
- Mechanical efficiency (ME) decreased as MA increased.
- Increased external power output (P(ext)) correlated with higher joint torques, particularly in shoulder flexion and adduction.
- Anterior deltoid and pectoralis muscles were identified as prime movers.
Conclusions:
- Shoulder muscles play a primary role in manual wheelchair propulsion.
- Elbow extensors did not show conclusive evidence for directing propulsive forces.
- Further research is needed on coordinative aspects and muscle function in closed-chain propulsion.
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