Electromyographic analysis of the tackle within rugby football

Abstract

EMG has previously been used to analyse muscle activation during shoulder rehabilitation programmes and during sports related activities There are no reports on the muscle activity around the shoulder during a standard tackle within rugby football, although there is epidemiological evidence stating that the incidence of injuries to the shoulder within professional rugby is between 0.5 and 1.0 per 1000 playing hours with several studies have highlighted the tackle as being the major cause of all injuries within rugby. The purpose of this study was to define the sequence of muscular activity in selected gleno and scapulo humeral muscles during a front on rugby football tackle. It is hoped then that this information can be utilised to develop muscle specific training and rehabilitation protocols, which may, ultimately minimise the incidence of injury, enhance sports-specific performance, and the career span of professional rugby players. Five healthy asymptomatic experienced Rugby Union players were examined. Surface EMG activity was assessed during a modified tackle activity against a tackle dummy. Onset of EMG activity was assessed in Pectorialis Major, Biceps Brachii, Latissimus Dorsi, Serratus Anterior and Infraspinatus relative to time of impact in the tackle. Onset of activity occurred in all muscles prior to impact. One way ANOVA showed significant differences between muscles in activation timing ( p = 0.0001 ), paired t -tests (with Bonferroni corrections) revealed that Serratus Anterior was activated prior to all other muscles tested ( p p > 0.05 ). These findings indicate consistent early activation of Serratus Anterior prior to impact, ahead of other muscles. Previous literature has reported decreased or inconsistent Serratus Anterior recruitment in swimmers with shoulder pathology, further research is required to discover if altered recruitment of Serratus Anterior is also related to shoulder injuries in rugby.