Gait retraining to reduce lower extremity loading in runners.
BACKGROUND
tibial stress fractures, which are among the most common running related injuries, have been associated with increased lower extremity loading (i.e., peak positive acceleration of the tibia, vertical force impact peak, and average and instantaneous vertical force loading rates) during initial contact. This study was conducted to evaluate the efficacy of a gait retraining program designed to reduce this loading during running and to assess the short-term persistence of these reductions.


METHODS
ten runners (six females and four males) with peak positive tibial acceleration greater than 8g, measured in an initial screening, participated in the retraining program. During the retraining sessions, subjects ran on a treadmill and received real-time visual feedback from an accelerometer attached to their distal tibias. Tibial acceleration and vertical ground reaction force data were collected from subjects during overground data collection sessions held pre-training, post-training, and at a 1-month follow-up.


RESULTS
peak positive acceleration of the tibia, vertical force impact peak, and average and instantaneous vertical force loading rates were all reduced immediately following the gait retraining. The decrease in tibial acceleration was nearly 50%. The reductions in vertical force loading rates and vertical force impact peak were approximately 30% and 20%, respectively. These reductions were maintained at the 1-month follow-up.


CONCLUSIONS
subjects were able to run with reduced tibial acceleration and vertical force loading immediately following completion of the gait retraining program and at the 1-month follow-up evaluation. This may reduce their risk of stress fractures.
Crowell
Harrison Philip
HP
US Army Research Laboratory-Human Research and Engineering Directorate, RDRL-HRS-B, Aberdeen Proving Ground, MD 21005-5425, USA. harrison.philip.crowell@us.army.mil
Davis
Irene S
IS
D000054:Acceleration; D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D015775:Fractures, Stress / Q000517:prevention & control*; D005684:Gait; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D012420:Running / Q000293:injuries*; D013314:Stress, Mechanical; D013977:Tibia / Q000293:injuries*; D013978:Tibial Fractures / Q000517:prevention & control; D013997:Time Factors