The Effect of Foot Orthoses on Energy Consumption in Runners with Flat Feet

Introduction Foot orthosis is used as protective treatment in people with flatfoot. This study aimed at assessing the effects of Foot orthosis on energy consumption in 20 runners with flat feet.Methods: In this study a treadmill and a Quark b2 were used to measure oxygen consumption. For each patient, a pair of foot orthosis with the appropriate size was prepared. The maximum running Heart rate, vo2 max and vo2 of the subjects were measured and calculated with and without foot orthoses. The data were compared through paired T-test.Results: In this study, after using the foot orthoses, the mean VO2 (ML/M), theVO2 max (ML/M for each Kg of body weight) and the maximum heart rate respectively reduced from 4504.6 to 4488.3, from 63.6 to 63.4 and from 168.7 to 168.0, all of which indicating a significant observed reduction (P<0.05).Conclusion: Foot support devices (orthoses) result in realignment of lower extremity joints in patients with flat feet, thus length- tension relationship of muscles improve. This prevents muscle fatigue in long- distance running. Finally, when suitable foot orthoses was applied energy consumption during running decreased.