Lumbo-pelvic loading during fast bowling in adolescent cricketers: The influence of bowling speed and technique

Abstract

This study aimed to assess changes in bowling technique and lumbar load over the course of a bowling spell in adolescent fast bowlers, and to investigate the relationship between lumbar loads during fast bowling and kinematic factors which have previously been associated with low back injury. Three-dimensional motion analysis was carried out on forty participants who performed an 8-over bowling spell. There were no significant changes in bowling technique or lumbar loads over the course of the spell. Bowling with a more extended front knee, faster ball release speed and increased shoulder counter-rotation were related to increased lumbo-pelvic loading – in particular peak transverse plane rotation moments and anterior-posterior shear forces. These lumbar loads may be a factor in low back injury aetiology and future studies should investigate the relationship between lumbar loading, injury incidence and other risk factors.     

Using and updating local norms

The most useful kind of norms are local norms collected by a test interpreter on a population with which s/he is familiar. We present a rationale for the use of local norms and a procedure, illustrated with an example, for updating a norm group's test score mean and variance. It was concluded that test interpreters should build local norms to be used in conjunction with norms based on a national sample, since local norms can be more recent, relevant, and representative for local groups.