Corticomuscular Adaptations in the Single-Leg Jump Task in Response to Progressive Mechanical Perturbation Training in Individuals With Anterior Cruciate Ligament Deficiency

Introduction: Studies have repeatedly discussed the importance of training with sufficient cognitive and sensory-motor challenges in successfully transferring Anterior Cruciate Ligament Deficiencies (ACLDs) from rehabilitation centers to sports facilities. For this purpose, this study investigated the effect of mechanical perturbation training and standard training on the brain and muscle activity of these individuals while jumping on one leg. Materials and Methods: A total of 30 athletes with unilateral Anterior Cruciate Ligament (ACL) rupture (in the coper classification) were randomly assigned to perturbation and standard training groups. To compare the effect of two types of intervention training methods, we examined the Similarity Index (SI) and Voluntary Response Index (VRI) in surface Electromyography (sEMG) tests of eight muscles in the lower extremities and relative power of alpha and beta spectra in Quantitative Electroencephalographic (QEEG) tests between two groups and between two limbs of each group members in the single-leg jump task. Results: Both training groups showed improved neuromuscular control and increased SI on sEMG tests between the two limbs. However, this improvement in the perturbation training group showed an excellent increase in Effect Size (ES) (intra-group comparison values of SI for perturbation training group P=0.0001, ES=3.6; and P=0.008, ES=1.24 in the standard training group; and P=0.04, ES=0.87 in the inter-group comparison). Regarding the post-test of QEEG tests, no significant difference was found between the two groups (alpha P-value: 0.13, beta P-value: 0.07). However, in the intra-group comparison, the perturbation training group achieved excellent symmetry for the relative power spectrum of alpha and beta signals (the similarity values between the two limbs in the perturbation training group for alpha were P=0.92, ES=0.04 and for beta were P=0.92, ES=0.02; and these values for standard training group for alpha were P=0.07, ES=0.86 and for beta as P=0.08, ES=0.87). Conclusion: The present study results showed that mechanical perturbation and standard training are suitable for transporting ACLDs to sports environments. Furthermore, in comparing these two training methods, mechanical perturbation training in the manner used in this study has higher adequacy to eliminate motor control and central nervous system defects.