To evaluate the balance strategies used during the wheelie balance phase we used potentiometers to record the relationship between rear-wheel displacement and pitch angle of 20 wheelie-capable participants. As a validation, classical motion analysis recorded the wheelchair kinematics of one subject who deliberately used both proactive and reactive balance strategies (PBS and RBS respectively). We found evidence of PBS in 18 (54.5%) of the 33 valid potentiometer trials. The pitch and displacement perturbations were opposite in direction with no apparent phase lags present and an approximate frequency range of 0.75-1.5 Hz. RBS was only identified in the motion analysis trials. Latencies between the onset of same direction pitch and displacement perturbations ranged from 0.37-1.25 seconds.
wheelchair, wheelie, rehabilitation, kinematics, electromyography
Kim Parker, CLFL
QEII Health Sciences Centre
1341 Summer Street
Halifax, Nova Scotia, B3H 4K4
(902) 473-2893.
This should be in the right column.