# Effectiveness of Lower-Cost Strategies for Running Gait Retraining: A Systematic Review
## 4 Discussion
There was a slight but non-significant decrease in the percentage of non- heel strike runners at the 6-month and 1-year follow-up. Runners also presented significant increases in cadence from the baseline to post-training (approximately 6%), from the baseline to 6 months (approximately 3.7%), and from the baseline to 1 year (approximately 4.2%) of follow-up. Therefore, it can be arguedthat there is strong evidence that clinicians, coaches, and researchers can confidently use video analysis to guide their gait retraining interventions for runners. Instrumented socks are a recently developed wearable technology that consist of a Bluetooth-enabled instrumented socks that can provide real-time biofeedback to runners [47]. When this device is paired with a smartphone, the user can receive real-time auditory and/or visual biofeedback on their foot strike pattern, cadence, running pace, total distance covered, and elevation changes. In a study by [PERSON] et al. [47], instrumented socks were used to detect the foot strike pattern using plantar pressure sensors and, through a smartphone application, provide real-time audio biofeedback on the distance covered, pace, foot strike pattern, and cadence for the runners who performed the retraining. In that study, the authors required that the runners not step on their heels, attempt to lean forward to step on the forefoot, and maintained a cadence of 180 steps/minute. The findings showed that 95% of the runners transitioned to a type of non-heel strike and that the majority (89%) maintained this transition in foot strike pattern after one month. In a study by [PERSON], [PERSON], and [PERSON] [56], instrumented socks with sensors were also used in the intervention to alter the foot strike pattern through visual feedback, and insoles instrumented with pressure sensors were used to determine the location of the center of pressure on initial contact of the foot with the ground. Initially, with a 10% increase in cadence, the authors obtained a modest anterior displacement of the center of pressure in the initial contact and consistent changes in relation to a lesser inclination of the foot in the initial contact, which corroborated other studies that used a 10% increase in cadence [24; 40; 42]. However, when there was a change in the foot strike pattern combined with an increase in cadence, the anterior displacement of the center of pressure was significantly more pronounced, which suggested that the average location of the center of pressure along the longitudinal axis of the insole changed by 192.7% in relation to the baseline. According to [PERSON] et al. [71], the sensor-instrumented socks demonstrated moderate reliability for the detection of the foot strike pattern and excellent reliability in determining cadence. In a study by [PERSON] et al. [59] that used insoles with sensors to collect cadence and peak force, it was identified that a 7.3% increase in cadence generated a decrease in the peak force of 5.6%. These results provided moderate evidence that the use of instrumented socks and insoles in running retraining to increase cadence and a non-heel strike pattern can improve important biomechanical factors related to injury risk. Pressure sensors were also used with a pressure platform in a study by [PERSON], [PERSON], and [PERSON] [57], who evaluated the effects of a running retraining strategy with feedback on the distribution of plantar pressure and plantar arch in runners who adopted a heel pattern. In that study, it was found that the group that received eight retraining sessions with visual feedback presented a reduction in plantar pressure on the heels, and the plantar arch during running showed a better adjustment in plantar support. These results demonstrated limited evidence for the use of the pressure platform in running retraining.