Ankle injuries in cricket fast bowlers are of topical interest with a number of elite pace bowlers recently sustaining injuries. Previous biomechanical research has concentrated on the injury risk to the fast bowler’s lumbar spine with no research focused on the leading leg and specifically the ankle biomechanics of the fast bowler and its predisposition to injury.

We investigate the leading leg biomechanics in maximal and submaximal fast bowling. Ten fast-medium paced bowlers of elite level had their leading leg biomechanics assessed during their bowling action. Using a nine camera infra-red ViconTM 612 motion analysis system linked to a KistlerTM 9281CA force platform the moments of the subjects leading leg during their delivery stride was analysed. Each subject performed ten trials at a maximal ball release speed (> 97km/hr) and ten trials at a submaximal ball release speed (< 97km/hr) with the speed of the ball tracked by a SR3600 radar gun.

All three large joints of the leg were observed and joint moments examined in both directions of all three orthogonal planes giving a total of eighteen joint moments investigated. Of these results only the difference in the ankle plantar flexion was found to be significant. The average ankle plantar flexion peak moment in the maximal and submaximal ball release speed groups were found to be 2.008Nm/kg and 1.790Nm/kg respectively. This difference was statistically significant (p< 0.02)

The increased ankle plantar moment reflects the important role the ankle plays in the generation of extra ball release speed in the fast bowler. However this role does place increased stress on the ankle which may predispose it to injury. This study suggests that the ankle plays a significant role in the fast bowler’s delivery action and post injury rehabilitation needs to take this into consideration.