kinetic

Introduction: This study aimed to investigate the effect of a 4-week core stability training program on landing kinetic parameters in athletes with functional ankle instability during a single-leg drop landing exercise. Methods: This study used a pre-post quasi-experimental design and was conducted in the biomechanics laboratory. A total number of 24 athletes with functional ankle instability participated in two experimental (n=12) and control (n=12) groups. The experimental group performed core stability training for 4 weeks. The kinetic variables (maximum vertical Ground-Reaction Force [GRF], maximum shear GRF, and time to peak vertical GRF) were measured with force plate at the frequency of 400 Hz, in the pre-test and post-test. The obtained data were compared using Analysis of Covariance (ANCOVA) and multivariate analysis of covariance MANCOVA in SPSS V. 18. Results: In the experimental group, all variables significantly differ between the pre-test and post-test. Also, the ANCOVA and MANCOVA indicated significant differences between the experimental and control groups in all variables. Conclusion: The results indicated that the core stability training improved the kinetic parameters of landing in people with functional ankle instability; thus, it can reduce the re-injury risk of the ankle.

Introduction: The return to sport after Anterior Cruciate Ligament Reconstruction (ACLR) is among the main issues encountered by rehabilitation medicine, injured athletes, and coaches. A main factor preventing safe return to sports is a biomechanical asymmetry between the limbs during reconstruction, which plays a significant role in the risk of re-injury. Accordingly, injury-related biomechanical changes were systematically examined in individuals with ACLR as performed functional tasks. Materials and Methods: Articles relevant to biomechanical asymmetries between (ACLR & uninjured) limbs in English were searched in the Google Scholar, Science Direct, PubMed MEDLINE, and Scopus databases without time limit until 2021, using the following keywords: “Anterior cruciate ligament reconstruction”, “ACL reconstruction”, “biomechanical”, “Kinetic”, “Kinematic”, and “Asymmetry”. Results: In total, 122 articles were found, of which 18 met the inclusion (PRISMA) criteria. Most of the kinetic and kinematic parameters were observed in the intervals of 3, 6, 9, 12, and 18 months after ACLR between the athletes’ vertical Ground Reaction Force (vGRF), peak hip abduction moment, peak knee valgus angle, peak knee flexion moment and angle, during the functional tasks; also changes were detected in the articles up to 28 months, although research in this area was limited. Conclusion: The present systematic review suggested that biomechanical variables may vary among the limbs of patients with ACLR, between 18 and over 28 months. Accordingly, an asymmetry between the limbs increases the risk of re-injury. Therefore, a better understanding of the biomechanics of the limbs in the time intervals after ACLR can provide a safer and sooner return to sports activities.

Introduction:This study aimed to compare selected kinetic factors during a cross-cutting maneuver in soccer players with athletics groin pain (AGP) and healthy-ones. Materials and Method: twenty-eight soccer players (healthy group (n=14) and AGP group (n=14)) who take-part in the first division league participated in this study. A force-plate via 1000 hertz sampling rate was used to evaluate the ground reaction force, rate of force developments, vertical-impulse, and symmetry index during the cross-cutting maneuver.The independent sample t-test used to compare the results between healthy groups with AGP. Results:The results indicated the significant differences in the peak of ground reaction force (P=0.023), symmetry index (P=0.01), and rate of force development (P=0.031) in the medial-lateral direction of the dominant limb in a group with AGP. The peak of the vertical ground reaction force of none dominant limb was significantly higher in the AGP group (P=0.004). Conclusion:It seems that groin pain changes the kinetic profile, which puts the athletes at the potential risk of overuse in the lower extremities injuries. It is also recommended to utilize the output of the current study as back to sports index, and the rehabilitation progress should be continued to reduce symptoms injuries up to the proper symmetry.