Context: Cricket fast bowlers are particularly susceptible to lumbar spine loading and injury. Quantitative analysis of technique typically involves laboratory-based biomechanical systems with limited ecological validity, whereas contemporary developments in GPS microtechnologies facilitate on-field evaluation of loading. Objective: To quantify the influence of sub-maximal bowling from reduced approach lengths on performance and loading. Design: Repeated measures, field-based. Setting: Regulation cricket pitch. Participants: 12 male cricket academy fast bowlers (18.7 ± 0.7 y), injury free with ≥3 years competitive experience. Interventions: Each bowler wore 2 GPS units placed at C7 and L4 to measure triaxial acceleration (100 Hz). Bowlers completed an over (six deliveries) from a randomised 3, 6, 9, and 12 stride approach. Main Outcome Measures: Ball speed was recorded as the performance measure, with PlayerLoad in the anteroposterior, mediolateral and vertical planes also calculated for each delivery length. Results: In ball speed there was a significant main effect for delivery length (P = 0.016), with a 3 stride approach eliciting significantly less ball speed than a 9 (P = 0.032) or 12 (P = 0.002) stride approach. In loading, there was a significant (P < 0.001) main effect for delivery length in the anteroposterior, mediolateral, and vertical planes, with loading increasing linearly as a function of delivery strides. The 6 stride approach elicited a 44% reduction in loading, with a disproportionately small 3.5% decrease in performance. There was a significant main effect for GPS location in all planes (P ≤ 0.023), with L4 eliciting greater loading than C7. Conclusions: A sub-maximal 6 stride approach yielded the optimum balance between reduced loading and performance inhibition. Reduced delivery length therefore offers an alternative to reduced overs in reducing loading in young bowlers, and might also have practicable value in the rehabilitation of bowlers post-injury.
|Journal||Journal of Sport Rehabilitation|
|Publication status||Accepted/In press - 28 Dec 2018|