Introduction: One of the known mechanisms in the occurrence of ACL ligament injuries is dynamic knee valgus, which neuromuscular exercises have been introduced as an efficient intervention in its prevention. Adding transcranial direct current stimulation (tDCS) can improve neuromuscular control by stimulating muscle recruitment. Therefore, the aim of this study was to determine the effect of 12 sessions of neuromuscular exercises with and without tDCS on changes in the electromyographic activity of the muscles controlling the knee in single squats and leg pairs of taekwondo athletes with dynamic knee valgus.
Methodology: Thirty-four martial artists suffering from dynamic knee valgus defect were purposefully selected and randomly assigned to two experimental and control groups. Both groups received three sessions of neuromuscular exercises per week for 4 weeks, with the difference that the experimental group received real stimulation and the control group received sham stimulation. Before and after 12 sessions of intervention, the electromyographic activity of the muscles controlling the knee was evaluated in double and single leg squat skills. Paired-sample t-test was used for intra-group comparisons and independent sample t-test was used for inter-group comparisons.
Results: Both experimental and control groups showed a significant improvement in dynamic valgus factor (p<0.05). However, intergroup comparisons did not show significant differences (p>0.05). Intra-group comparisons showed that in both groups, the activity of all muscles (except the external biceps muscle in the control group and in single-leg squat skills) improved significantly (p<0.05). But inter-group comparisons showed that the two study groups in paired squat skills only in lateral vestus muscle activity (p=0.02) and gluteus maximus (p=0.02) and in single leg squat task only in lateral vestus muscle activity (p=0.001) ) and the lateral twin (p=0.05) were statistically significantly different.
Conclusion: After 12 sessions, both groups were able to significantly improve the amount of dynamic valgus and the activity of knee controlling muscles in double and single leg squat tasks. In the paired squat only in the activity of the vastus external and gluteus maximus muscles, in the single leg squat only in the activity of the external vastus and quadriceps muscles, a statistically significant difference was seen between the two groups. This was while the calculation of the percentage of changes in all the factors of the real stimulation group was more effective.