Neuromuscular and biomechanical characteristic changes in high school athletes: a plyometric versus basic resistance program

Abstract

Background: In order to improve neuromuscular and biomechanical characteristic deficits in female athletes, numerous injury prevention programs have been developed and have successfully reduced the number of knee ligament injuries. However, few have investigated the neuromuscular and biomechanical changes following these training programs. It is also largely unknown what type of program is better for improving the landing mechanics of female athletes. Objectives: To investigate the effects of an 8 week plyometric and basic resistance training program on neuromuscular and biomechanical characteristics in female athletes. Methods: Twenty seven high school female athletes participated either in a plyometric or a basic resistance training program. Knee and hip strength, landing mechanics, and muscle activity were recorded before and after the intervention programs. In the jump-landing task, subjects jumped as high as they could and landed on both feet. Electromyography (EMG) peak activation time and integrated EMG of thigh and hip muscles were recorded prior to (preactive) and subsequent to (reactive) foot contact. Results: Both groups improved knee extensor isokinetic strength and increased initial and peak knee and hip flexion, and time to peak knee flexion during the task. The peak preactive EMG of the gluteus medius and integrated EMG for the gluteus medius during the preactive and reactive time periods were significantly greater for both groups. Conclusions: Basic training alone induced favourable neuromuscular and biomechanical changes in high school female athletes. The plyometric program may further be utilised to improve muscular activation patterns.

Differences in Lower Extremity Kinematics Between a Bilateral Drop-Vertical Jump and A Single-Leg Step-down

“…This should be further investigated in a future study. Knee flexion angles reported in this study are similar to those previously reported for a drop-vertical jump 5,17,20,22 and for a step-down task. 43 Our hypothesis of greater knee abduction in the step-down task was not supported.…”

“…Hip adduction angles in this study are smaller than those reported previously for a drop-vertical jump task, running, or cutting. 5,8,17,20,22,23,27,34 Zeller et al 43 reported hip adduction joint angles during a single-leg squat to be about 12° for males and about 16° for females. The interaction of gender and task for hip Step-down internal rotation indicated that there was greater hip internal rotation in the step-down than the drop-vertical jump for females; but for males there was no difference between tasks.…”

Muscle Strength in the Lower Extremity Does Not Predict Postinstruction Improvements in the Landing Patterns of Female Athletes

“…4 These neuromuscular risk factors are particularly interesting to rehabilitation specialists, as they represent factors that may be amendable to training intervention. In fact, ACL injury prevention programs have had success in correcting potentially risky landing patterns 10,14,20,26 and also in reducing the rate of injury in female athletes. 7,16,22 Not all training programs have had significant success in reducing ACL injury rates, and female athletes may not universally experience the same magnitude of landing pattern improvement.…”

Prevention and Management of Post-operative Complications Following ACL Reconstruction

“…Given the fact that many ACL tears are noncontact in nature, these patients likely exhibit poor neuromuscular control and biomechanical deficits. In general, ACL prevention programs which include a combination of dynamic warm up, strengthening, agility, balance, and plyometric activities have been shown to have good short-term effectiveness [44][45][46][47][48]. These activities all involve elements of neuromuscular training, in addition to demonstrating the potential to reduce the number of ACL injuries.…”