Sports Performance, Recovery, Injury and New Technologies (SPRINT) Research Centre, Australian Catholic University, Melbourne, Australia.
School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, Australia; and.
J Strength Cond Res. 2024 Feb 1;38(2):283-289. doi: 10.1519/JSC.0000000000004614. Epub 2023 Oct 25.
Horsley, BJ, Tofari, PJ, Halson, SL, Kemp, JG, Johnston, RD, and Cormack, SJ. Thoracic-worn accelerometers detect fatigue-related changes in vertical stiffness during sprinting. J Strength Cond Res 38(2): 283-289, 2024-Thoracic-mounted accelerometers are valid and reliable for analyzing gait characteristics and may provide the opportunity to assess running-related neuromuscular fatigue (NMF) during training and competition without the need for additional tests, such as a countermovement jump (CMJ). However, their sensitivity for detecting fatigue-related changes in gait across different speeds is unclear. We, therefore, assessed the changes in accelerometer-derived gait characteristics, including vertical stiffness (K vert ), following a repeated sprint protocol (RSP). Sixteen recreationally active subjects performed single and repeated CMJs on a force plate and 40 m run throughs overground at 3-4, 5-6, and 7-8 m·s -1 pre-post a 12 × 40 m RSP. Gait characteristics (contact time, step frequency, step length, K vert , etc.) were derived from an accelerometer contained within a global navigation satellite system unit on the thoracic spine using a validated algorithm. Changes in running gait and CMJ performance were assessed using a linear mixed-effects model (95% confidence interval [95% CI]; effect size [ES]). Significance was set at p < 0.05. A significant reduction in K vert occurred at 7-8 m·s -1 following the RSP (-8.51 kN·m -1 [-13.9, -3.11]; p = 0.007; ES [95% CI] = -0.39 [-0.62, -0.15]) which coincided with a decreased jump height (-0.03 m [-0.04, -0.01]; p = 0.002; ES [95% CI] = -0.87 [-1.41, -0.30]). However, all other gait characteristics were not significantly different irrespective of speed. Thoracic-worn accelerometers can detect changes in K vert at 7-8 m·s -1 which may be useful for monitoring NMF during sprinting. However, a RSP does not result in altered gait mechanics in subsequent running at lower speeds.
霍斯利，BJ，托法里，PJ，哈尔森，SL，坎普，JG，约翰斯顿，RD 和科马克，SJ。胸带式加速度计可检测冲刺过程中垂直刚度与疲劳相关的变化。《力量与调节研究杂志》38（2）：283-289，2024-胸带式加速度计可用于分析步态特征，并且在训练和比赛中无需进行其他测试（如反跳测试）即可评估与跑步相关的神经肌肉疲劳（NMF），具有有效性和可靠性。然而，其检测不同速度下与疲劳相关的步态变化的敏感性尚不清楚。因此，我们评估了在重复冲刺方案（RSP）后，加速度计得出的步态特征（包括垂直刚度（K vert ））的变化。16 名休闲运动员在力板上进行单次和重复的反跳测试，并在进行 12×40 米 RSP 前后以 3-4、5-6 和 7-8 m·s -1 的速度在地面上进行 40 米跑步。使用经过验证的算法，从位于胸椎的全球导航卫星系统单元内的加速度计中得出步态特征（接触时间、步频、步长、K vert 等）。使用线性混合效应模型（95%置信区间[95%CI]；效应大小[ES]）评估跑步步态和反跳测试性能的变化。设定显著性水平为 p < 0.05。RSP 后，7-8 m·s -1 的 K vert 显著降低（-8.51 kN·m -1 [-13.9，-3.11]；p = 0.007；ES [95%CI] = -0.39 [-0.62，-0.15]），与跳跃高度降低（-0.03 m [-0.04，-0.01]；p = 0.002；ES [95%CI] = -0.87 [-1.41，-0.30]）同时发生。然而，无论速度如何，其他所有步态特征均无显著差异。胸带式加速度计可以检测到 7-8 m·s -1 时 K vert 的变化，这对于监测冲刺时的 NMF 可能很有用。但是，RSP 不会导致后续较低速度跑步时的步态力学发生改变。
