Three-Dimensional Pushrim Forces During Different Racing Wheelchair Propulsion Speeds

Three-dimensional kinematic and physiological data were obtained from 18 wheelchair racers, to allow the relationship between pushing economy and kinematic variables at 4.70 m · s−1(n= 18) and 6.58 m · s−1(n= 12) to be examined. Large inter individual differences in wheelchair propulsion styles were present, which made it difficult to identify variables that were associated with pushing economy and indeed to distinguish key variables that were characteristic of an economical wheelchair racer. Furthermore, those variables associated with economy proved inconsistent across the two speeds. However, at both speeds a higher mechanical efficiency and lower push rate were associated with better economy (p< .05). It was also found that the timing parameters were important. In this respect most athletes tended to push through a similar push angle; however, push rate differed between individuals, suggesting that the magnitude and direction of the hand-rim forces may be important for determining economy of propulsion.

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General Uncertainty Analysis for Manual Wheelchair Propulsion Dynamics and Development of an Instrumented Wheel

Journal of Medical Devices ◽

10.1115/1.2735970 ◽

2006 ◽

Vol 1 (2) ◽

pp. 140-150

Author(s):

M. Mallakzadeh ◽

F. Sassani

Keyword(s):

Uncertainty Analysis ◽

Angular Position ◽

Three Dimensional ◽

Published Data ◽

Wheelchair Propulsion ◽

Wheelchair User ◽

Wheelchair Users ◽

Manual Wheelchair ◽

Taylor Series Expansions ◽

Propulsion Phase

Manual wheelchair propulsion (MWP) is an inefficient and physically straining process. A reliably fabricated and instrumented wheel can help researchers to accurately calculate the forces and moments exerted by the wheelchair users and propose strategies to improve MWP. In this study, an instrumented wheel is designed, fabricated, and validated by using general uncertainty analysis. A six-component transducer is used to measure three-dimensional forces and moments applied by the wheelchair user on the handrim. The output of the transducer are forces and moments, which are directly transmitted to a PC using a USB port. By developing the transformation equations, the actual forces and moments on the hand of the wheelchair user are calculated. The angular position of the hand on the handrim is calculated from the kinetic data obtained through the instrumented wheel, and the derived equations. The general uncertainty analysis method is used to calculate the uncertainty values for the variables of interest with the Taylor series expansions. An analysis of the results shows that it is possible to obtain reliable information for MWP by using the instrumented wheel. Most of the data have uncertainties under 5% during much of the propulsion phase, and the patterns and overall behavior of the results are comparable to published data.

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Three-Dimensional Kinematic Analysis and Physiologic Assessment of Racing Wheelchair Propulsion

Adapted Physical Activity Quarterly ◽

10.1123/apaq.15.1.1 ◽

1998 ◽

Vol 15 (1) ◽

pp. 1-14 ◽

Cited By ~ 18

Author(s):

Thomas J. O’Connor ◽

Rick N. Robertson ◽

Rory A. Cooper

Keyword(s):

Stepwise Regression ◽

Three Dimensional ◽

Maximum Speed ◽

Wheelchair Propulsion ◽

Wheelchair Athletes ◽

Medium Speed ◽

Preparatory Phase ◽

Wrist Trajectory ◽

Track Athletes ◽

Hand Contact

Three-dimensional kinematic variables and their relationship to the physiology of racing wheelchair propulsion were studied. Six male wheelchair athletes performed two trials (medium and maximum speed) of 3 min each. VO2, VO2/kg, VE, and HR were measured. Results showed that at medium speed, wrist velocity on hand contact was significantly correlated with VO2/kg. At maximum speed, elbow velocity during preparatory phase was significantly correlated with VO2. Stepwise regression showed wrist trajectory angle and elbow velocity during preparatory phase were significantly correlated with VO2/kg. Results indicate that kinematic variables recorded prior to and on hand contact with the pushrim are significant variables in developing a more efficient racing wheelchair propulsion technique. Results of this study indicate a need to educate coaches of wheelchair track athletes concerning the best racing wheelchair propulsion technique.

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Three dimensional upper extremity motion during manual wheelchair propulsion in men with different levels of spinal cord injury

Gait & Posture ◽

10.1016/s0966-6362(99)00034-x ◽

1999 ◽

Vol 10 (3) ◽

pp. 223-232 ◽

Cited By ~ 44

Author(s):

Craig J Newsam ◽

Sreesha S Rao ◽

Sara J Mulroy ◽

JoAnne K Gronley ◽

Ernest L Bontrager ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Upper Extremity ◽

Three Dimensional ◽

Wheelchair Propulsion ◽

Manual Wheelchair ◽

Cord Injury ◽

Extremity Motion ◽

Different Levels

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Force Application During Handcycling and Handrim Wheelchair Propulsion: An Initial Comparison

Journal of Applied Biomechanics ◽

10.1123/jab.29.6.687 ◽

2013 ◽

Vol 29 (6) ◽

pp. 687-695 ◽

Cited By ~ 18

Author(s):

Ursina Arnet ◽

Stefan van Drongelen ◽

DirkJan Veeger ◽

Lucas H. V. van der Woude

Keyword(s):

Power Output ◽

Three Dimensional ◽

Wheelchair Propulsion ◽

Force Application ◽

Initial Comparison ◽

Applied Forces

The aim of the study was to evaluate the external applied forces, the effectiveness of force application and the net shoulder moments of handcycling in comparison with handrim wheelchair propulsion at different inclines. Ten able-bodied men performed standardized exercises on a treadmill at inclines of 1%, 2.5% and 4% with an instrumented handbike and wheelchair that measured three-dimensional propulsion forces. The results showed that during handcycling significantly lower mean forces were applied at inclines of 2.5% (P< .001) and 4% (P< .001) and significantly lower peak forces were applied at all inclines (1%:P= .014, 2.5% and 4%:P< .001). At the 2.5% incline, where power output was the same for both devices, total forces (mean over trial) of 22.8 N and 27.5 N and peak forces of 40.1 N and 106.9 N were measured for handbike and wheelchair propulsion. The force effectiveness did not differ between the devices (P= .757); however, the effectiveness did increase with higher inclines during handcycling whereas it stayed constant over all inclines for wheelchair propulsion. The resulting peak net shoulder moments were lower for handcycling compared with wheelchair propulsion at all inclines (P< .001). These results confirm the assumption that handcycling is physically less straining.

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