Department of Biomechanics and Sport Injury, Faculty of Physical Education and Sports Sciences, Kharazmi University, Tehran 1571914911, Iran.
Department for Training and Movement Science, Johannes Gutenberg-University Mainz, 55122 Mainz, Germany.
Int J Environ Res Public Health. 2022 Aug 15;19(16):10052. doi: 10.3390/ijerph191610052.
The current study aimed to compare the possible effects of differential learning strategy, self-controlled feedback, and external focus of attention on kinetic and kinematic risk factors of anterior cruciate ligament (ACL) injury in athletes. Forty-eight male athletes from three sports of handball, volleyball and basketball were selected for this study and were randomly divided into four groups: differential learning ( = 12), self-control feedback ( = 12), external focus ( = 12), and control ( = 12) group. All groups followed the intervention for eight weeks with three sessions per week. Data were analyzed by means of 4 × 2 repeated measures ANOVA followed by post hoc comparison (Bonferroni) at the significance level of ≤ 0.05. A significant group × time interaction and the main effect of time was found for most kinetic and kinematic variables. The main effect of the group was significant only at the knee abduction angle. Differential learning and external focus of attention methods positively reduced the kinetic and kinematic variables that are considered risk factors for ACL injury. However, the effect sizes (Cohen's d) for the changes in most of the variables were larger for the differential learning group. Tailoring the boundary conditions that are based on the manipulations created in the exercise through variability and variety of movements associated with differential learning methods rather than repeating movements could reduce the risk of ACL injury.
本研究旨在比较不同学习策略、自我控制反馈和外部注意焦点对运动员前交叉韧带（ACL）损伤运动学和运动学风险因素的可能影响。本研究选取了来自手球、排球和篮球三个运动项目的 48 名男性运动员，并将他们随机分为四个组：差异学习组（ = 12）、自我控制反馈组（ = 12）、外部注意焦点组（ = 12）和对照组（ = 12）。所有组均接受 8 周的干预，每周 3 次。采用 4×2 重复测量方差分析，随后进行事后比较（Bonferroni），显著性水平设为 ≤ 0.05。大多数动力学和运动学变量均发现组间×时间交互作用和时间的主效应显著。组的主效应仅在膝关节外展角度上显著。差异学习和外部注意焦点方法可积极降低被认为是 ACL 损伤风险因素的动力学和运动学变量。然而，对于大多数变量的变化，差异学习组的效应大小（Cohen's d）更大。通过变异性和与差异学习方法相关的运动多样性来调整基于练习中产生的操作的边界条件，而不是重复运动，可以降低 ACL 损伤的风险。
