Thompson Steve W, Lake Jason P, Rogerson David, Ruddock Alan, Barnes Andrew
Academy for Sport and Physical Activity, Sheffield Hallam University, Sheffield, United Kingdom ; and.
Department of Sport and Exercise Sciences, Chichester University, Chichester, United Kingdom.
J Strength Cond Res. 2023 Jan 1;37(1):1-8. doi: 10.1519/JSC.0000000000004186. Epub 2022 Jan 5.
Thompson, SW, Lake, JP, Rogerson, D, Ruddock, A, and Barnes, A. Kinetics and kinematics of the free-weight back squat and loaded jump squat. J Strength Cond Res 37(1): 1-8, 2023-The aim of this study was to compare kinetics and kinematics of 2 lower-body free-weight exercises, calculated from concentric and propulsion subphases, across multiple loads. Sixteen strength-trained men performed back squat 1 repetition maximum (1RM) tests (visit 1), followed by 2 incremental back squat and jump squat protocols (visit 2) (loads = 0% and 30-60%, back squat 1RM). Concentric phase and propulsion phase force-time-displacement characteristics were derived from force plate data and compared using analysis of variance and Hedges' g effect sizes. Intrasession reliability was calculated using intraclass correlation coefficient (ICC) and coefficient of variation (CV). All dependent variables met acceptable reliability (ICC >0.7; CV < 10%). Statistically significant 3-way interactions (load × phase × exercise) and 2-way main effects (phase × exercise) were observed for mean force, velocity (30-60% 1RM), power, work, displacement, and duration (0%, 30-50% 1RM) ( p < 0.05). A significant 2-way interaction (load × exercise) was observed for impulse ( p < 0.001). Jump squat velocity ( g = 0.94-3.80), impulse ( g = 1.98-3.21), power ( g = 0.84-2.93), and work ( g = 1.09-3.56) were significantly larger across concentric and propulsion phases, as well as mean propulsion force ( g = 0.30-1.06) performed over all loads ( p < 0.001). No statistically significant differences were observed for mean concentric force. Statistically longer durations ( g = 0.38-1.54) and larger displacements ( g = 2.03-4.40) were evident for all loads and both subphases ( p < 0.05). Ballistic, lower-body exercise produces greater kinetic and kinematic outputs than nonballistic equivalents, irrespective of phase determination. Practitioners should therefore use ballistic methods when prescribing or testing lower-body exercises to maximize athlete's force-time-displacement characteristics.
汤普森，S.W.，莱克，J.P.，罗杰森，D.，拉多克，A.，以及巴恩斯，A. 自由重量后深蹲和负重跳深蹲的动力学与运动学。《力量与体能研究杂志》37(1): 1 - 8，2023年——本研究的目的是比较两种下肢自由重量练习的动力学与运动学，这些数据是根据多个负荷下的向心和推进子阶段计算得出的。16名经过力量训练的男性进行了后深蹲1次最大重复量（1RM）测试（第1次就诊），随后进行了2次递增的后深蹲和跳深蹲方案（第2次就诊）（负荷 = 0%和30 - 60%的后深蹲1RM）。向心阶段和推进阶段的力 - 时间 - 位移特征从测力台数据中得出，并使用方差分析和赫奇斯g效应量进行比较。使用组内相关系数（ICC）和变异系数（CV）计算了组内可靠性。所有因变量的可靠性均达到可接受水平（ICC > 0.7；CV < 10%）。对于平均力、速度（30 - 60% 1RM）、功率、功、位移和持续时间（0%，30 - 50% 1RM），观察到了具有统计学意义的三因素交互作用（负荷×阶段×练习）和两因素主效应（阶段×练习）（p < 0.05）。对于冲量，观察到了具有统计学意义的两因素交互作用（负荷×练习）（p < 0.001）。在向心和推进阶段，跳深蹲的速度（g = 0.94 - 3.80）、冲量（g = 1.98 - 3.21）、功率（g = 0.84 - 2.93）和功（g = 1.09 - 3.56）均显著更大，以及在所有负荷下的平均推进力（g = 0.30 - 1.06）也显著更大（p < 0.001）。向心平均力未观察到统计学上的显著差异。对于所有负荷和两个子阶段，统计学上更长的持续时间（g = 0.38 - 1.54）和更大的位移（g = 2.03 - 4.40）是明显的（p < 0.05）。无论阶段如何确定，弹道式的下肢练习比非弹道式的等效练习能产生更大的动力学和运动学输出。因此，从业者在规定或测试下肢练习时应采用弹道式方法，以最大化运动员的力 - 时间 - 位移特征。
