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 (n = 12), self-control feedback (n = 12), external focus (n = 12), and control (n = 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 p ≤ 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.

Variation during practice is widely accepted to be advantageous for motor learning and is, therefore, a valuable strategy to effectively reduce high-risk landing mechanics and prevent primary anterior cruciate ligament (ACL) injury. Few attempts have examined the specific effects of variable training in athletes who have undergone ACL reconstruction. Thereby, it is still unclear to what extent the variations in different sensor areas lead to different effects. Accordingly, we compared the effects of versatile movement variations (DL) with variations of movements with emphasis on disrupting visual information (VMT) in athletes who had undergone ACL reconstruction. Forty-five interceptive sports athletes after ACL reconstruction were randomly allocated to a DL group (n = 15), VT group (n = 15), or control group (n = 15). The primary outcome was functional performance (Triple Hop Test). The secondary outcomes included dynamic balance (Star Excursion Balance Test (SEBT)), biomechanics during single-leg drop-landing task hip flexion (HF), knee flexion (KF), ankle dorsiflexion (AD), knee valgus (KV), and vertical ground reaction force (VGRF), and kinesiophobia (Tampa Scale of Kinesiophobia (TSK)) assessed before and after the 8 weeks of interventions. Data were analyzed by means of 3 × 2 repeated measures ANOVA followed by post hoc comparison (Bonferroni) at the significance level of p ≤ 0.05. Significant group × time interaction effects, main effect of time, and main effect of group were found for the triple hop test and all eight directions, SEBT, HF, KF, AD, KV, VGRF, and TSK. There was no significant main effect of group in the HF and triple hop test. Additionally, significant differences in the triple hop test and the seven directions of SEBT, HF, KF, KV, VGRF, and TSK were found between the control group and the DL and VMT groups. Between group differences in AD and the medial direction of SEBT were not significant. Additionally, there were no significant differences between VMT and the control group in the triple hop test and HF variables. Both motor learning (DL and VMT) programs improved outcomes in patients after ACL reconstruction. The findings suggest that DL and VMT training programs lead to comparable improvements in rehabilitation.

Variable during practice is widely accepted to be advantageous for motor learning and therefor a valuable strategy to effectively reduce high-risk landing mechanics and prevent primary anterior cruciate ligament (ACL) injury. Few attempts have examined the specific effects of variable train-ing in athletes who have undergone ACL reconstruction. Thereby it is still unclear to what extent the variations in different sensor areas lead to different effects. Accordingly, we compared the effects of versatile movement variations (DL) with variations of movements with emphasis on disrupting visual information (VMT) in athletes who had undergone ACL reconstruction. For-ty-five interceptive sports athletes after ACL reconstruction were randomly allocated to a DL group (n= 15), VT group (n= 15) or control group (n= 15). The primary outcome was functional performance (Triple Hop Test). The secondary outcomes included dynamic balance (Star Excur-sion Balance Test (SEBT)), biomechanics during single-leg drop-landing task hip flexion (HF), knee flexion (KF), ankle dorsiflexion (AD), knee valgus (KV), and vertical ground reaction force (VGRF), and kinesiophobia (Tampa Scale of Kinesiophobia (TSK)) assessed before and after the 8-weeks of interventions. Data were analyzed be means of 3×2 repeated measures ANOVA fol-lowed by post hoc comparison (Bonferroni) at the significance level of p≤0.05. Significant group × time interaction effects, main effect of time and main effect of group were found for triple hop test, all eight directions of SEBT, HF, KF, AD, KV, VGRF and TSK. There was no significant main ef-fect of group in HF and triple hop test. Also, significant differences in triple hop test, seven direc-tions of SEBT, HF, KF, KV, VGRF and TSK were found between control group with the DL and VMT groups. Between group differences in AD and medial direction of SEBT were not signifi-cant. Also, there was no significant differences between VMT and control groups in triple hop test and HF variables. Both motor learning (DL and VMT) programs improved outcomes in patients after ACL reconstruction. Findings suggest that DL and VMT training programs lead to compa-rable improvements in rehabilitation.

Introduction: A potential limitation of current ACL injury prevention training may be a deficit in the transfer of conscious, optimal movement strategies rehearsed during training sessions to automatic movements required for athletic activities. Instructional strategies with an internal focus of attention have traditionally been utilized, but may not be optimal for the ...

Background and Aims According to studies, motor learning instructions and strategies have been effective in anterior cruciate ligament (ACL) injury prevention programs. Therefore, the current study aimed to study the effect of motor learning strategies on landing biomechanics in athletes with dynamic knee valgus. Methods This study was a quasi-experimental and applied research. 48 male athletes aged 20-25, participating in handball, volleyball, and basketball, with a dynamic knee valgus angle greater than 10 degrees, were randomly assigned to four groups(n=12): Differential learning, self-controlled feedback, external focus of attention, and control. The training program lasted eight weeks, with three sessions per week for the first six weeks and two sessions per week for the last two weeks. Each session was 45 minutes long. Using motion analysis and EMG systems, kinematics and kinetics parameters during landing were measured. To analyze the data, 4×2 repeated measures ANOVA was directed, followed by post hoc comparison (Bonferroni) at the significant level of P≤0.05. Results The present study showed an increase in peak hip and knee flexion angles, a decrease in peak knee abduction angle, and an increase in gluteus medius feedforward activity from the pre-test to post-test in differential learning and external focus of attention groups. Also, the differential learning group observed an increase from the pre-test to post-test values of peak dorsiflexion angle and gluteus maximus feedforward activity. In between-groups comparison, there was a significant difference between the differential, control, and self-control feedback groups in peak knee flexion and abduction angles. Also, the differential learning group showed a significant difference in gluteus medius feedforward activity compared to the control group. Conclusion Differential learning and external focus of attention methods positively reduced the kinetic and kinematic risk factors of ACL injury. However, the results of the present study consider the differential learning method and the role of variability in training to be effective in preventing ACL injury and suggest the differential learning method for the greater benefit of athletes.

Background and Aims Dynamic knee valgus is recognized as one of the most significant risk factors for anterior cruciate ligament (ACL) injuries. Common strategies to prevent dynamic knee valgus and ACL injuries include taping and visual feedback techniques. This study aimed to compare the immediate effects of taping and visual feedback methods on kinematic risk factors in male athletes exhibiting dynamic knee valgus. Methods This study was quasi-experimental. 34 athletes aged 20-25 years with dynamic knee valgus were purposefully selected and randomly assigned to taping and visual feedback groups. Kinovea software was utilized to screen for dynamic knee valgus during a 32-cm drop landing task. Both study groups performed double-leg squats, single-leg squats, forward step-downs, and lateral step-downs under taping and visual feedback conditions. In the taping method, an “I” shaped tape was applied from the tibial tuberosity to the medial and lateral femoral condyles to restrict anterior tibial translation. Participants in the visual feedback group stood in front of a full-length mirror. They were instructed to prevent their knees from moving towards the midline of their body while visually monitoring their alignment. Knee and hip flexion angles, knee valgus, and ankle dorsiflexion angles were measured using an IMU system before and after the exercise intervention. A two-way repeated measures analysis of variance was employed to analyze the data at a significance level of P≤0.05. Results The results of this study indicated a significant increase in peak knee (P=0.001) and hip (p=0.004) flexion angles from the pre-test to post-test in the visual feedback group. Furthermore, the visual feedback group (P=0.001) and the taping group (P=0.001) showed a significant decrease in peak knee valgus angle from pre-test to post-test phase. In between-group comparisons, the visual feedback group compared to the taping group showed a significant increase in peak knee flexion (P= 0.001) and hip flexion (P=0.039) angles and a significant decrease in peak knee valgus angle (P=0.001). Conclusion Both visual feedback and taping interventions positively reduced kinematic risk factors for ACL injury. However, the visual feedback group demonstrated a larger effect size on most variables than the taping group. This study’s findings support visual feedback’s effectiveness in controlling knee valgus and mitigating kinematic risk factors for ACL injury. Therefore, visual feedback is recommended for athletes seeking to reduce their risk of ACL injury.