title: Gait retraining to reduce lower extremity loading in runners.
abstract: 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.
authors.affiliation: 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
authors.forename: Harrison Philip
authors.initials: HP
authors.lastname: Crowell
authors.forename: Irene S
authors.initials: IS
authors.lastname: Davis
mesh_terms: 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