Factors affecting performance in elite finger-spin bowling

Abstract

Full-body three-dimensional kinematics, passive joint range of motion and bowling parameters from match play were calculated to enable the analysis of elite finger spin bowling technique and delivery mechanics. Specifically, the effect of kinematic parameters and passive joint range of motion contributing to the production of spin were examined whilst ball trajectory parameters in international test match cricket were assessed and the extent to which these parameters may impact match performance. Kinematic and passive range of motion data were collected for a group of 23 elite finger spin bowlers, describing elements of finger spin bowling technique with the effect of these parameters on ball spin rate addressed using linear regression. Ball trajectory data were collected using a Hawk-eyeTM ball tracking system for 36 elite finger spin bowlers competing in international test match cricket between 2006 – 2015. Parameters were calculated describing elements of ball trajectory with the effect of these parameters on bowling average and economy addressed using linear regression. Kinematic analysis suggests the bowlers imparting the most spin adopted a mid-way pelvis orientation angle, a larger pelvis-shoulder separation angle and a shoulder orientation short of side-on at FFC. The orientation of the pelvis at FFC was shown to be the most important technique parameter explaining 43.1% of the variance in ball spin rate. Higher ball spin rates were also associated with a larger internal rotation of the rear hip and bowling shoulder, whilst the total arc of rotation of the non-dominant hip (front leg) was found to be the best predictor of ball spin rate, explaining 26% of the observed variance in spin rate. Side to side differences were also observed with greater external rotation and lesser internal rotation in the bowling shoulder, and greater internal rotation in the non-dominant hip. Linear regressions of bowling parameters in test match competition revealed bowling length, bowing line and release velocity as the biggest predictors of bowling economy, predicting 54.4% of the observed variance. Findings suggest bowlers conceding the least runs released the ball at higher ball release speeds, bowled straight bowling lines and pitched the ball 4 – 5m in length. Whilst no parameters were predictive of bowling average, results indicate that deliveries deviating away from the opposing batsman concede less runs and takes more wickets, when compared to deviating toward.