Int J Sports Physiol Perform. 2020 Sep 29;15(10):1485-1489. doi: 10.1123/ijspp.2019-0622.
To investigate whether changes in delivery length (ie, short, good, and full) lead to alterations in whole-body biomechanical loading as determined by ground reaction force during front-foot contact of the delivery stride for pace bowlers. Current load-monitoring practices of pace bowling in cricket assume equivocal biomechanical loading as only the total number of deliveries are monitored irrespective of delivery length.
A total of 16 male pace bowlers completed a 2-over spell at maximum intensity while targeting different delivery lengths (short, 7-10 m; good, 4-7 m; and full, 0-4 m from the batter's stumps). In-ground force plates were used to determine discrete (vertical and braking force, impulse, and loading rates) and continuous front-foot contact ground reaction force. Repeated-measures analysis of variance (P < .05), effects size, and statistical parametrical mapping were used to determine differences between delivery lengths.
There were no significant differences between short, good, and full delivery lengths for the discrete and continuous kinetic variables investigated (P = .19-1.00), with trivial to small effect sizes.
There were minimal differences in front-foot contact biomechanics for deliveries of different lengths (ie, short, good, and full). These data reinforce current pace bowling load-monitoring practices (ie, counting the number of deliveries), as changes in delivery length do not affect the whole-body biomechanical loading experienced by pace bowlers. This is of practical importance as it retains simplicity in load-monitoring practice that is used widely across different competition levels and ages.
研究投球步前脚触地时的地面反作用力是否会因投球长度(即短球、好球和满球)的变化而改变,以确定投球手的全身生物力学负荷。板球投球目前的负荷监测实践假设生物力学负荷是等效的,因为只监测总投球次数,而不管投球长度如何。
16 名男性投球手在最大强度下完成了 2 个投球回合,目标是不同的投球长度(短球,7-10 米;好球,4-7 米;满球,0-4 米)。使用埋入式测力板确定离散(垂直力和制动力、冲量和加载率)和连续前脚触地地面反作用力。使用重复测量方差分析(P <.05)、效应量和统计参数映射来确定投球长度之间的差异。
在研究的离散和连续动力学变量方面,短球、好球和满球的投球长度之间没有显著差异(P =.19-1.00),效应量为小到中等。
不同长度(即短球、好球和满球)的投球前脚触地生物力学差异很小。这些数据支持当前的投球负荷监测实践(即计数投球次数),因为投球长度的变化不会影响投球手的全身生物力学负荷。这在实践中非常重要,因为它保留了在不同比赛水平和年龄段广泛使用的简单的负荷监测实践。