Comparing the Effects of Differential and Visuo-Motor Training on Functional Performance, Biomechanical, and Psychological Factors in Athletes after ACL Reconstruction: A Randomized Controlled Trial.

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.

Comparing the Effects of Differential Learning, Self-Controlled Feedback, and External Focus of Attention Training on Biomechanical Risk Factors of Anterior Cruciate Ligament (ACL) in Athletes: A Randomized Controlled Trial.

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.

Examining the Influence of Attentional Focus on the Effects of a Neuromuscular Training Program in Male Athletes.

ABSTRACT: Ghanati, HA, Letafatkar, A, Almonroeder, TG, and Rabiei, P. Examining the influence of attentional focus on the effects of a neuromuscular training program in male athletes. J Strength Cond Res 36(6): 1568-1575, 2022-Neuromuscular training programs that incorporate lower extremity strengthening, plyometric exercises, balance training, and movement retraining are recommended for anterior cruciate ligament injury prevention; however, there is a need to improve their effectiveness. The purpose of this study was to examine how athletes' attentional focus during training influences the effects of an 8-week neuromuscular training program on hip strength, single-leg landing mechanics, and hop performance. Sixty-six male athletes were randomly allocated to a group that trained with an internal focus, a group that trained with an external focus, or a control group. All athletes completed testing before (baseline) and after (posttesting) the 8-week period. Isokinetic hip strength, hip and knee kinematics and ground reaction forces during landing, and hop distance were examined as part of this study. Analysis of covariance was used to compare posttesting outcomes among the groups while accounting for group differences in baseline performance. The neuromuscular training program resulted in improved hip abduction strength, reduced hip adduction and internal rotation motion during landing, and increased hop distance for athletes who trained with an external focus. However, the program did not seem to influence hip strength, landing kinematics, or hop performance for athletes who trained with an internal focus. Our findings indicate that male athletes may benefit from completing a neuromuscular training program with an external focus vs. an internal focus. Trainers, coaches, and clinicians should consider using instructions that promote an external focus when implementing neuromuscular training programs with male athletes.