Jump test asymmetry profiles of elite trials cyclists.

Bike trials is a cycling discipline in which riders navigate a series of obstacle courses on their bikes. As many of the techniques used in trials riding are acyclic, riders will display a natural preference as to which foot is on the front pedal. The primary aim of this study was to try to identify if this unique riding style creates a sport-specific inter-limb asymmetry profile during a range of common jump tests. Eight elite trials riders (mean age 20.0 ± 0.9 years, height 178.5 ± 6.8 cm, weight 76.1 ± 10.4 kg) completed three repetitions each of countermovement jump, single leg countermovement jump and single leg hop tests. There were no significant asymmetries between the overall group means for the jump tests (absolute asymmetry: countermovement jump 5.4 ± 3.6%; single leg countermovement jump 10.0 ± 5.4%; and single leg hop 5.9 ± 4.0%). There were however significant (p<0.05) individual asymmetries found in all of the jump tests and meaningful asymmetries (percentage asymmetry greater than coefficient of variation) in both of the single leg tests. The direction of asymmetry was shown to be variable across the different tests (Fleiss’ Kappa = -0.34). Some participants also showed meaningful and significant differences in the movement strategies used within a test, though again there were no significant differences in the group means. The findings suggest inter-limb asymmetries are highly task specific and there was no evidence to suggest that trials riders develop specific asymmetries due to the asymmetrical physical demands of their sport.