The effects of core stabilization exercises on the neuromuscular function of athletes with ACL reconstruction.

Athletes who have undergone anterior cruciate ligament reconstruction (ACLR) often exhibit persistently impaired kinematics and strength. Core stability training appears to be effective for reducing high-risk landing mechanics and preventing primary anterior cruciate ligament (ACL) injuries; however, there have been few attempts to examine their effects in athletes who have undergone ACLR. This study aimed to investigate the effect of eight weeks of simple core stability training on core endurance, hip strength, and knee kinematics in ACLR athletes. Twenty-six male athletes (20-30 years old) with a history of ACL surgery with hamstring tendon autograft were randomly divided into training (n = 13) and control groups (n = 13). The training group performed core stability exercises for eight weeks before starting their team training; the control group did not receive any intervention. Both groups continued their regular team schedule. The core endurance, hip muscle strength, and knee kinematics were assessed by the McGill test, a hand-held dynamometer, and video-taping, respectively. Analysis of covariance test was used for data analysis. The training group showed a significant increase in core endurance, hip abductor and external rotator strength, knee flexion angle, and a significant decrease in the knee valgus angle during single-leg landing in post-training tests compared to their baseline tests (P < 0.05). Our results demonstrated that core stability exercise alters neuromuscular function to a level that is clinically acceptable and statistically significant. Because of the high incidence rate of secondary ACL injury after ACLR, it is recommended that athletes with a history of ACLR benefit from adding core stability exercises to warm-up routines or tertiary prevention programs even after completing post-operative rehabilitation. It is fast and not time-consuming to perform for athletes to reduce the risk factors of re-injury. Trial registration: This study was registered in the Iranian Registry of Clinical Trials with the number IRCT20190224042827N2, registered on 19 December 2019.

Cold-Water Immersion and Sports Massage Can Improve Pain Sensation but Not Functionality in Athletes with Delayed Onset Muscle Soreness.

This study aimed to investigate the effects of cold-water immersion (CWI) and sports massage on delayed-onset muscle soreness (DOMS) in amateur athletes. Sixty male amateur athletes were randomised into four equal groups (n = 15) receiving either CWI, sports massage, their combination, or served as controls after applying plyometric training to their lower extremities. The main outcomes measures were pain, exertion, rectus femoris perimeter, knee flexion range of motion, knee extensors isometric strength and serum creatine phosphokinase (CPK) levels examined before the plyometric training, immediately after the treatment, and 24, 48 and 72 h post exercise. We observed no significant differences between study groups in the most tested variables. CWI improved pain compared to the combined application of CWI and sports massage, and the control group both on the second and third day post exercise. Sports massage combined with CWI also led to a significant reduction in pain sensation compared to the control group. In conclusion the treatment interventions used were effective in reducing pain but were unable to affect other important adaptations of DOMS. Based on the above, sports scientists should reconsider the wide use of these interventions as a recovery strategy for athletes with DOMS.

Female athletes with ligament dominance exhibiting altered hip and ankle muscle co-contraction patterns compared to healthy individuals during single-leg landing.

BACKGROUND: Anterior cruciate ligament (ACL) injury is one of the most serious knee injuries and occurs frequently during exercise. Altered hip and ankle muscle co-contraction patterns may contribute to dynamic knee valgus and ACL injury mechanisms. Lack of dynamic control of ground reaction force (GRF) is known to be contributing factor for ACL injury by placing excessive force on passive structures. Muscle co-contraction is a dynamic mechanism for GRF absorption. Therefore, any alterations in co-contraction might be a risk factor for ACL injury. Ligament dominance is a term to define individuals who rely more on ACL ligament for GRF control. RESEARCH QUESTION: This study aimed to compare the muscle co-contraction patterns of distal and proximal knee muscles during single leg landing in female athletes with and without ligament dominance. METHODS: This is a cross-sectional study. A total of 54 female athletes were assigned to the healthy (n = 27) and ligament dominance (n = 27) group based on their Tuck Jump test scores. The electromyography activity of the gluteus medius, adductor longus, tibialis anterior, peroneus longus, medial and lateral gastrocnemius was measured by an electromyography in drop down a 30-cm-high stair. A Multivariate Analysis of Variance (MANOVA) was used for statistical analysis (p ≤ 0.05). RESULTS: The two groups demonstrated an overall significantly different muscle co-contraction patterns (P < 0.05). There was a decreased in co-contraction of proximal group and an increased co-contraction in the distal muscles in ligament dominant group. SIGNIFICANCE: The findings have provided evidence to support the notion of neuromuscular imbalances in ligament dominance deficit. These findings can be useful for the coaches and experts to design preventive exercises and modify the current programs for the people affected by ligament dominance.

The effects of gluteus medius and tibialis anterior kinesio taping on postural control, knee kinematics, and knee proprioception in female athletes with dynamic knee valgus.

OBJECTIVES: This study aimed to investigate the effects of Kinesio taping on postural control, kinematics, and knee proprioception in female athletes with dynamic knee valgus (DKV). DESIGN: a single-blind randomized clinical trial. PARTICIPANTS: 40 female athletes between the age of 18 and 28 years with DKV in single-leg drop landing (>13°) participated in this study. They were randomly classified into the Kinesio taping (KT) and placebo control (PC) groups. MAIN OUTCOME MEASURES: All the evaluations and measurements were performed on each subject in the pre-test and post-test stages (with an interval of 72 h). The dynamic balance (Y balance test), proprioception (Knee position sense error), and knee kinematics (flexion and DKV angles) of the subjects were measured, prior and post gluteus medius and tibialis anterior KT. RESULTS: The results of study demonstrate that the DKV angle and knee position sense error significantly decreased and YBT increased in the KT group from pre-test to post-test (p < 0.05). Nevertheless, there was no significant difference in knee flexion angle (p > 0.05). CONCLUSION: The results of the present study indicated that KT improves dynamic balance and proprioception and reduces the DKV angle. Therefore, KT is recommended for female athletes with DKV.

Anatomical risk factors of lateral ankle sprain in adolescent athletes: A prospective cohort study.

OBJECTIVES: The purpose of this study was to identify prospectively the anatomical and functional intrinsic risk factors for lateral ankle sprain (LAS) in adolescent athletes participating in team sports. DESIGN: A prospective cohort study. SETTING: University research laboratory. PARTICIPANTS: A total of 152 adolescent male athletes (age: 14.45 ± 2.96 years; height: 165.63 ± 15.33 cm; weight: 55.60 ± 16.56 kg; body mass index: 19.97 ± 3.58 kg/m2) participated in this study. MAIN OUTCOME MEASURES: The participants were assessed during the preseason for previous ankle sprain history, navicular drop, tibia vara, Q angle, tibia torsion, knee recurvatum, and ankle ROM. LASs were prospectively recorded and diagnosed for two consecutive seasons (20 months). RESULTS: Previous ankle sprain history (odds ratio [OR] = 60.911, p < 0.001), increased navicular drop (OR = 1.767, p < 0.001), and knee recurvatum (OR = 1.881, p = 0.002) were positively associated with the incidence of LAS. The receiver operating characteristic (ROC) analyses revealed the predictive potentials of previous ankle sprain history (the area under the ROC [AUROC] = 0.706, p < 0.001), navicular drop (AUROC = 0.906, p < 0.001), and knee recurvatum (AUROC = 0.724, p < 0.001). CONCLUSION: Athletes with previous ankle sprain history, knee recurvatum, and especially navicular drop may have a greater risk of LAS injury. The data from this study can help therapists and trainers to identify people with a higher risk of LAS.