Effect of Whole-Body Vibration on Sagittal Plane Running Mechanics in Individuals With Anterior Cruciate Ligament Reconstruction: A Randomized Crossover Trial.

OBJECTIVE: To examine the effect of whole-body vibration (WBV) on running biomechanics in individuals with anterior cruciate ligament reconstruction (ACLR).

DESIGN: Single-blind randomized crossover trial.

SETTING: Research laboratory.

PARTICIPANTS: Individuals (N=20) with unilateral ACLR (age [± SD]=22.3 [±3.3] years; mass=71.8 [±15.3] kg; time since ACLR=44.9 [±22.8] months; 15 females, 10 patellar tendon autograft, 7 hamstrings autograft, 3 allograft; International Knee Documentation Committee Score=83.5 [±9.3]).

MAIN OUTCOME MEASURE: Participants performed isometric squats while being exposed to WBV or no vibration (control). WBV and control conditions were delivered in a randomized order during separate visits separated by 1-week washout periods. Running biomechanics of the injured and uninjured limbs were evaluated before and immediately after each intervention. Dependent variables included peak vertical ground reaction force (GRF) and loading rate (LR), peak knee flexion angle and external moment, and knee flexion excursion during the stance phase of running.

RESULTS: There was an increase in knee flexion excursion (+4.1°, 95% confidence interval [CI]: 0.65, 7.5°) and a trend toward a reduction in instantaneous LR after WBV in the injured limb (-4.03 BW/sec-1 , 95% CI -0.38, -7.69). No effect was observed on peak GRF, peak knee flexion angle, or peak external knee flexion moment, and no effect was observed in the uninjured limb.

CONCLUSIONS: Our findings indicate that a single session of WBV acutely increases knee flexion excursion. WBV could be useful to improve running characteristics in individuals with knee pathology.