Real-time biofeedback to target risk of anterior cruciate ligament injury: a technical report for injury prevention and rehabilitation.

CONTEXT: Biofeedback training enables an athlete to alter biomechanical and physiological function by receiving biomechanical and physiological data concurrent with or immediately after a task.

OBJECTIVE

To compare the effects of 2 different modes of real-time biofeedback focused on reducing risk factors related to anterior cruciate ligament injury.

DESIGN

Randomized crossover study design.

SETTING

Biomechanics laboratory and sports medicine center.

PARTICIPANTS

Female high school soccer players (age 14.8 ± 1.0 y, height 162.6 ± 6.8 cm, mass 55.9 ± 7.0 kg; n = 4).

INTERVENTION: A battery of kinetic- or kinematic-based real-time biofeedback during repetitive double-leg squats.

MAIN OUTCOME MEASURES: Baseline and posttraining drop vertical jumps were collected to determine if either feedback method improved high injury risk landing mechanics.

RESULTS

Maximum knee abduction moment and angle during the landing was significantly decreased after kinetic-focused biofeedback (P = .04). The reduced knee abduction moment during the drop vertical jumps after kinematic-focused biofeedback was not different (P = .2). Maximum knee abduction angle was significantly decreased after kinetic biofeedback (P < .01) but only showed a trend toward reduction after kinematic biofeedback (P = .08).

CONCLUSIONS

The innovative biofeedback employed in the current study reduced knee abduction load and posture from baseline to posttraining during a drop vertical jump.