London Sport Institute, Middlesex University, Greenlands Lane, London, United Kingdom.
Brighton Football Club Academy, Brughton, UK.
J Strength Cond Res. 2022 Jun 1;36(6):1660-1666. doi: 10.1519/JSC.0000000000003679. Epub 2020 Jun 5.
Bishop, C, Abbott, W, Brashill, C, Turner, A, Lake, J, and Read, P. Bilateral vs. unilateral countermovement jumps: comparing the magnitude and direction of asymmetry in elite academy soccer players. J Strength Cond Res 36(6): 1660-1666, 2022-The aims of this study were to compare the magnitude and direction of asymmetry in comparable bilateral and unilateral countermovement jumps (CMJs). Forty-five elite academy soccer players from under-23 (n = 15), under-18 (n = 16), and under-16 (n = 14) age groups performed bilateral and unilateral CMJs as part of their routine preseason fitness testing. For the magnitude of asymmetry, no significant differences were evident for any metric between tests. However, the eccentric impulse asymmetry was significantly greater than mean force and concentric impulse in both bilateral and unilateral tests (p < 0.01). For the direction of asymmetry, Kappa coefficients showed poor levels of agreement between test measures for all metrics (mean force = -0.15, concentric impulse = -0.07, and eccentric impulse = -0.13). The mean jump data were also presented relative to the body mass for each group. For the bilateral CMJ, significant differences were evident between groups but showed little consistency in the same group performing better or worse across metrics. For the unilateral CMJ, eccentric impulse was the only metric to show meaningful differences between groups, with the under-18 group performing significantly worse than under-23 and under-16 players. This study highlights that despite the magnitude of asymmetry being similar for each metric between comparable bilateral and unilateral CMJs, consistency in the direction of asymmetry was poor. In essence, if the right limb produced the larger force or impulse during a bilateral CMJ, it was rare for the same limb to perform superior during the unilateral task. Thus, practitioners should be aware that bilateral and unilateral CMJs present different limb dominance characteristics and should not use 1 test to represent the other when measuring between-limb asymmetries.
毕晓普、C、阿博特、W、布拉希尔、C、特纳、A、雷克、P。双侧与单侧反向跳跃：比较精英学院足球运动员双侧与单侧反向跳跃的幅度和不对称方向。J 力量与体能研究 36(6)：1660-1666，2022-本研究的目的是比较双侧和单侧反向跳跃（CMJ）的幅度和不对称方向。45 名来自 23 岁以下（n = 15）、18 岁以下（n = 16）和 16 岁以下（n = 14）年龄组的精英学院足球运动员作为其常规季前体能测试的一部分进行了双侧和单侧 CMJ。对于不对称幅度，在测试之间，任何指标都没有明显差异。然而，在双侧和单侧测试中，离心冲量的不对称性明显大于平均力和向心冲量（p < 0.01）。对于不对称方向，所有指标的测试测量之间的 Kappa 系数显示出较差的一致性（平均力=-0.15，向心冲量=-0.07，离心冲量=-0.13）。平均跳跃数据也根据每个组的体重进行了呈现。对于双侧 CMJ，在组间存在明显差异，但在同一组中，同一组在各项指标上表现更好或更差的一致性很小。对于单侧 CMJ，离心冲量是唯一显示出组间有意义差异的指标，18 岁以下组的表现明显不如 23 岁以下和 16 岁以下的球员。本研究表明，尽管在每个指标的双侧和单侧 CMJ 之间的不对称幅度相似，但在不对称方向上的一致性很差。从本质上讲，如果在双侧 CMJ 中右腿产生的力或冲量大，那么右腿在单侧任务中表现更好的情况很少见。因此，从业者应该意识到，双侧和单侧 CMJ 表现出不同的肢体优势特征，在测量肢体间不对称时，不应该用 1 个测试来代表另一个测试。
