Gait Retraining Can Modify Biomechanical Variables In Injured Runners

Previous research has identified aspects of running biomechanics as potential risk factors for running-related injuries (RRIs). Gait retraining has been proposed as a method to alter biomechanics to address RRIs. Although previous studies have demonstrated that gait retraining can modify aspects of biomechanics associated with RRIs, limited work has evaluated changes in running biomechanics after gait retraining for injured runners. PURPOSE: To investigate changes in vertical ground reaction force (vGRF), vertical average loading rate (VALR), vertical instantaneous loading rate (VILR), cadence, and foot strike pattern, following running gait retraining program. METHODS: 39 runners with RRIs completed a baseline running gait analysis. Each completed structured physical therapy to address impairments identified at baseline followed by supervised gait retraining using a faded feedback design. Discharge running gait analysis was performed to evaluate changes in biomechanics following gait retraining. Biomechanical data were collected at a self-selected speed in habitual footwear using motion capture and an instrumented treadmill and processed using a custom MATLAB code. Two tailed, paired t-tests were used to analyze continuous variables and McNemar-Bowker tests were used to analyze categorical variables. RESULTS: There was a significant increase in cadence and decrease in bilateral VALR and VILR following gait retraining, while the majority of runners transitioned from a rearfoot strike to a non-rearfoot strike pattern. (Table 1) Table 1. - Running Biomechanics Pre and Post Gait Retraining (n = 39) Variable Pre Post P value vGRF (Left) 2.28 BW 2.26 BW .587 vGRF (Right) 2.29 BW 2.27 BW .440 VALR (Left) 58.24 BW/s 39.59 BW/s <.001* VALR (Right) 60.36 BW/s 40.96 BW/s <.001* VILR (Left) 67.57 BW/s 51.89 BW/s <.001* VILR (Right) 69.22 BW/s 54.73 BW/s <.001* Cadence (steps/min) 164.8 170.2 <.001* Foot strike pattern 68.4% RFS, 15.8% MFS, 15.8% FFS 31.6% RFS, 5.3% MFS, 63.2% FFS <.001* RFS, rearfoot strike; MFS, midfoot strike, FFS, forefoot strike. Results expressed as mean or percentages. *statistical significance at α < 0.05 CONCLUSIONS: Our results suggest that a gait retraining program as part of supervised physical therapy can result in changes in biomechanics of interest, including increased cadence and reduced load rates in runners with RRIs. Future research should explore the most effective methods of gait retraining utilized in the clinic that result in optimal patient outcomes.