Int J Sports Physiol Perform. 2021 Jul 1;16(7):974-984. doi: 10.1123/ijspp.2020-0423. Epub 2021 Jan 13.
Concentric hip and eccentric knee joint mechanics affect sprint performance. Although the biarticular hamstrings combine these capacities, empirical links between swing phase mechanics and corresponding isokinetic outcome parameters are deficient. This explorative study aimed (1) to explain the variance of sprint velocity, (2) to compare maximal sprints with isokinetic tests, (3) to associate swing phase mechanics with isokinetic parameters, and (4) to quantify the relation between knee and hip joint swing phase mechanics.
A total of 22 sprinters (age = 22 y, height = 1.81 m, weight = 77 kg) performed sprints and eccentric knee flexor and concentric knee extensor tests. All exercises were captured by 10 (sprints) and 4 (isokinetics) cameras. Lower-limb muscle balance was assessed by the dynamic control ratio at the equilibrium point.
The sprint velocity (9.79 [0.49] m/s) was best predicted by the maximal knee extension velocity, hip mean power (both swing phase parameters), and isokinetic peak moment of concentric quadriceps exercise (R2 = 60%). The moment of the dynamic control ratio at the equilibrium point (R2 = 39%) was the isokinetic parameter with the highest predictive power itself. Knee and hip joint mechanics affected each other during sprinting. They were significantly associated with isokinetic parameters of eccentric hamstring tests, as well as moments and angles of the dynamic control ratio at the equilibrium point, but restrictedly with concentric quadriceps exercise. The maximal sprints imposed considerably higher loads than isokinetic tests (eg, 13-fold eccentric knee joint peak power).
Fast sprinters demonstrated distinctive knee and hip mechanics in the late swing phase, as well as strong eccentric hamstrings, with a clear association to the musculoarticular requirements of the swing phase in sprinting. The transferability of isokinetic knee strength data to sprinting is limited inter alia due to different hip joint configurations. However, isokinetic tests quantify specific sprint-related muscular prerequisites and constitute a useful diagnostic tool due to their predicting value to sprint performance.
髋关节的向心收缩和膝关节的离心收缩力学会影响短跑表现。虽然双关节腘绳肌具备这两种能力，但摆动阶段力学与相应等速测试结果参数之间的经验联系仍有所欠缺。本探索性研究旨在：（1）解释短跑速度的变化；（2）比较最大冲刺速度与等速测试结果；（3）将摆动阶段力学与等速测试参数联系起来；（4）量化膝关节和髋关节摆动阶段力学之间的关系。
共有 22 名短跑运动员（年龄=22 岁，身高=1.81 米，体重=77 千克）进行了短跑和离心膝屈肌及向心膝伸肌测试。所有运动都通过 10 个（短跑）和 4 个（等速）摄像机进行捕捉。通过平衡位置的动态控制比评估下肢肌肉平衡。
短跑速度（9.79[0.49]m/s）可由最大膝关节伸展速度、髋关节平均功率（均为摆动阶段参数）和向心股四头肌等速峰值力矩最佳预测（R2=60%）。平衡位置动态控制比的力矩（R2=39%）是自身预测能力最高的等速参数。在短跑过程中，膝关节和髋关节力学相互影响。它们与离心腘绳肌测试的等速参数、动态控制比的力矩和角度显著相关，但与向心股四头肌运动的相关性有限。最大冲刺比等速测试产生的负荷大得多（例如，离心膝关节峰值功率的 13 倍）。
快速短跑运动员在摆动后期表现出独特的膝关节和髋关节力学特征，以及强大的离心腘绳肌，与短跑摆动阶段的肌肉关节要求有明显的关联。等速膝关节力量数据向短跑的转化受到限制，部分原因是髋关节结构不同。然而，等速测试量化了与短跑相关的特定肌肉先决条件，并且由于其对短跑表现的预测价值，构成了一种有用的诊断工具。
