A comparison between intermittent and constant wheelchair propulsion strategies

The purpose of this study was to investigate the effect of different synchronous push strategies on physiological parameters and temporal timing characteristics. Eight novice male able-bodied participants completed four counter-balanced conditions: two push strategies (constant pushing) and intermittent pushing (INT) at two push frequencies (40 and 70 pushes/min) at 27 W. The ANOVA main effects for frequency indicated that regardless of push strategy, oxygen cost and mechanical efficiency increased with an increase in push frequency (p < 0.01). The INT40 strategy resulted in the lowest heart rate (115 +/- 19 beats/min). With increased frequency the push angle was reduced (91 degrees vs. 78 degrees respectively) and the push was initiated at a more anterior position of the wheel (p < 0.05). The results suggest that regardless of push strategy, the over-riding factor that influences both the physiological and timing parameters measured was push frequency.