The effects of four different stroke patterns on manual wheelchair propulsion and upper limb muscle strain

To evaluate the effects of stroke pattern on handrim biomechanics and upper limb electromyography (EMG) in experienced wheelchair users.

Subjects propelled their own wheelchair on a level, motor-driven treadmill using each of four identified stroke patterns: arcing, double loop (DL), semi-circular (SC) and single loop (SL). Upper limb EMG and measurements taken from an instrumented wheelchair wheel were compared for each pattern. A one-way ANOVA with Bonferroni correction (p < 0.05) was used to check for significant differences.

The DL and SC patterns produced the best overall results. The DL pattern led to a significantly longer contact angle and significantly less braking moment than the SL and arcing patterns, and a significantly lower cadence than the SL pattern. The SC pattern led to a significantly longer contact angle than the SL pattern and the lowest peak force and impact of any pattern. There were no significant differences in integrated EMG (IEMG); however, the DL and arcing patterns produced lower combined IEMG values.

When traversing level terrain, wheelchair users should push with either the DL or SC patterns. Between the two, the DL pattern required less muscle activity and may be a better choice for experienced wheelchair users.