Hip adduction and abduction strength and adduction-to-abduction ratio changes across an Australian Football League season

Abstract

ObjectivesPre-season hip strength testing only represents the athlete’s level of conditioning at that time point, and may change over an Australian Football (AF) season. This study aimed to examine if there are changes in hip adduction, abduction and the adduction-to-abduction ratio between preferred and non-preferred kicking legs throughout an AF season. The influence of training load and player characteristics was also examined. DesignCross-sectional repeated measures. Methods38 uninjured elite AF players were included. Maximal isometric hip adduction and abduction strength were measured at four time points: start of pre-season (T1), end of pre-season (T2), mid-season (T3) and post-season (T4) using a hand held dynamometer with external belt fixation. ResultsHip adduction strength and hip-adduction-to-abduction ratio were greater in T3 compared to T1 (adduction by 22.71N, p<0.001, ratio by 0.15N, p<0.001) and hip adduction and abduction were weaker in T4 compared to T1 (adduction by 18.6N, p=0.004, abduction by 24.67N, p<0.001). No differences were found between the preferred and non-preferred leg in adduction (p=0.409) or abduction (p=0.602) strength. There was an interaction between leg and time point for the adduction-to-abduction ratio; at T3 and T4, the ratio of the preferred kicking leg was significantly lower than the non-preferred kicking leg (T3 by 0.14N, p=0.020, T4 by 0.15N, p=0.019). Training load was not significantly associated with strength changes. ConclusionsHip strength does change over an AF season. Regular in-season hip strength testing should occur to more accurately reflect player condition compared to one pre-season measurement.