Department of Kinesiology, California State University-Fullerton, Fullerton, CA,USA.
UGA Concussion Research Laboratory, Department of Kinesiology, University of Georgia, Athens, GA,USA.
J Sport Rehabil. 2023 Jan 30;32(4):353-360. doi: 10.1123/jsr.2022-0252. Print 2023 May 1.
Induced mental fatigue negatively impacts sport performance and neurocognition. However, it is unclear how induced mental fatigue influences landing biomechanics. The purpose of this study was to examine the influence of mental fatigue on drop landing biomechanics in individuals with and without a concussion history.
Crossover design.
Forty-eight (24 per group) recreationally active individuals were matched on age (±3 y), sex, and body mass index (±1 kg/m2). All participants completed an experimental (30-min Stroop task) and control (30-min reading magazines) intervention on separate days separated by a minimum of 24 hours. Drop landings were performed before and after both interventions. Outcomes included peak vertical ground reaction force (vGRF), vertical loading rate (VLR), knee flexion angle, knee abduction angle, external knee flexion moment, external knee abduction moment, and initial ground contact knee flexion and knee abduction angles. Separate 2 (group) × 2 (intervention) between-within analyses of covariance compared drop landing outcomes. Each group's average pre-Stroop and premagazine outcomes were covariates.
There was a significant interaction for vGRF (P = .033, ηp2=.097) and VLR (P = .0497, ηp2=.083). The vGRF simple effects were not statistically significantly (P range = .052-.325). However, individuals with a concussion history displayed a medium effect size for greater vGRF post-Stroop compared with their own postmagazine vGRF (mean difference (95% confidence interval [95% CI] = 0.163 (-0.002 to 0.327) bodyweight (BW), p =.052, ηp2=.081. In contrast, the control group displayed a small effect size (mean difference [95% CI] = 0.095 [-0.069 to 0.259] BW, p =.251, ηp2=.029). Individuals with a concussion history displayed greater VLR post-Stroop compared with controls (mean difference [95% CI], 26.29 [6.19 to 46.40] BW/s, P = .012, ηp2=.134) and their own postmagazine values (mean difference [95% CI] = 32.61 [7.80 to 57.42] BW/s, p =.011, ηp2=.135).
Mental fatigue leads to greater VLR for individuals with a concussion history. Athletic competition and activities of daily living can increase mental fatigue. Training programs may seek to teach mental fatigue reducing strategies to athletes with a concussion history.
诱导性精神疲劳会对运动表现和神经认知产生负面影响。然而，诱导性精神疲劳如何影响着陆生物力学尚不清楚。本研究的目的是研究精神疲劳对有和无脑震荡史个体的落地生物力学的影响。
交叉设计。
48 名（每组 24 名）有休闲活动的个体根据年龄（±3 岁）、性别和体重指数（±1kg/m2）进行匹配。所有参与者在两天内分别完成了实验（30 分钟的斯特鲁普任务）和对照（30 分钟阅读杂志）干预，两次干预之间至少间隔 24 小时。在两次干预前后都进行了降落试验。结果包括峰值垂直地面反作用力（vGRF）、垂直加载率（VLR）、膝关节屈曲角度、膝关节外展角度、膝关节外展力矩、膝关节外展力矩和初始地面接触膝关节屈曲角度和膝关节外展角度。使用 2（组）×2（干预）的协方差分析比较了降落试验结果。每个组的平均斯特鲁普前和杂志前结果为协变量。
vGRF（P=.033，ηp2=.097）和 VLR（P=.0497，ηp2=.083）存在显著的交互作用。vGRF 的简单效应没有统计学意义（P 范围=.052-.325）。然而，有脑震荡史的个体在斯特鲁普后表现出较大的 vGRF，与他们自己的杂志后 vGRF 相比（平均差异（95%置信区间[95%CI] = 0.163（-0.002 至 0.327）体重（BW），p =.052，ηp2=.081）。相比之下，对照组显示出较小的效应大小（平均差异（95%CI）= 0.095（-0.069 至 0.259）BW，p =.251，ηp2=.029）。有脑震荡史的个体在斯特鲁普后显示出较大的 VLR，与对照组相比（平均差异[95%CI]，26.29[6.19 至 46.40]BW/s，P=.012，ηp2=.134）和他们自己的杂志后值（平均差异[95%CI] = 32.61[7.80 至 57.42]BW/s，p =.011，ηp2=.135）。
精神疲劳导致有脑震荡史的个体 VLR 增加。竞技比赛和日常生活活动会增加精神疲劳。训练计划可能会试图向有脑震荡史的运动员传授减少精神疲劳的策略。
