Running gait retraining has been reported to reduce lower-extremity loads and the risk for some running-related injuries. This has provided evidence that distance running gait can safely be modified in runners. Optimal running gait at a given speed is the product of anthropometric, neuromuscular, fatigue, and external factors. Because running biomechanics are integrally linked with economy, a major determinant of endurance running performance, it is conceivable that gait retraining could improve performance. The evidence investigating the influence of gait retraining on running economy will be evaluated and potential applications discussed.