Landing instructions focused on pelvic and trunk lateral tilt decrease the knee abduction moment during a single-leg drop vertical jump.

OBJECTIVES

To investigate the effects of pelvic and trunk lateral tilt-focused landing instructions on the knee abduction moment during the single-leg drop vertical jump task.

DESIGN

Descriptive laboratory study.

SETTING

Motion analysis laboratory.

PARTICIPANTS

Fifteen young, healthy female participants.

MAIN OUTCOME MEASURES: The participants performed 15 single-leg drop vertical jumps. Landing instructions with self-video recordings were provided so that the participants' pelvis and trunk remained horizontal in the frontal plane. Pelvic, trunk and knee kinematics and kinetics were evaluated using a three-dimensional motion analysis system before and after the landing instructions.

RESULTS

The peak knee abduction moment significantly decreased postinstruction (preinstruction 22.6 ± 15.3 Nm, postinstruction 17.9 ± 15.4 Nm, P = 0.004), as did pelvic and trunk lateral tilt (P < 0.01). The knee abduction and internal rotation angles at initial contact significantly decreased postinstruction (P = 0.037, P = 0.007), with no significant change in the peak knee abduction and internal rotation angles from pre-to postinstruction.

CONCLUSIONS

Landing instructions focused on pelvic and trunk lateral tilt are effective in decreasing the knee abduction moment during the single-leg drop vertical jump. Pelvic and trunk lateral tilt should be controlled to decrease the knee abduction moment during single-leg landing.