Randomized controlled trial.OBJECTIVES:
To determine the effects of instruction to improve frontal plane knee biomechanics during a jump-landing task.BACKGROUND:
Technique training is a common component of knee injury-prevention programs. In developing programs that minimize time commitment and increase the likelihood of adoption by target groups, there is a need to evaluate individual program components.METHODS:
A total of 26 female recreational athletes (average age, 21.2 years), who presented with medial knee displacement during a jump-landing task, completed the study protocol. Participants were randomly placed into 1 of 2 groups, an experimental or control group. The experimental group received instructions aimed at improving knee abduction during jump landings. The control group received a sham training. Prior to training, baseline kinematics and kinetics (peak knee abduction angle, peak internal knee adductor moment, knee flexion excursion, peak internal knee extensor moment, and peak vertical ground reaction force) were obtained from participants while performing a basketball rebound task. Immediate (5 minutes postinstruction) and delayed (15-20 minutes postinstruction) retention tests were performed within the instructional session. Two additional retention tests were performed following home-based training (1 and 2 weeks following the initial training).RESULTS:
The initial instructional session resulted in greater knee flexion excursion (9°) and a 20% reduction in the peak internal knee adductor moment in the experimental group. Following home-based training, the experimental group continued to exhibit increased knee flexion excursion, along with decreased peak vertical ground reaction forces. No biomechanical changes were observed in the control group for any of the retention tests when compared to baseline.CONCLUSION:
The jump-training instructions employed in the current study resulted in kinematic and kinetic changes in the sagittal plane as opposed to the frontal plane.LEVEL OF EVIDENCE:
Prevention, level 2b-.