G-18 Free Communication/Poster - Gait Analysis: MAY 30, 2009 7:30 AM - 11:00 AM ROOM: Hall 4F
Differences in kinematics of the lower extremity between a forefoot (FF) and rearfoot (RF) strike pattern may alter the metabolic demands of running. The FF strike pattern has been characterized by increased plantarflexion and inversion at touch down, greater rearfoot motion, increased knee internal rotation velocity and decreased ground contact time. It has been suggested that the kinematic profile of a FF strike pattern may reduce the metabolic cost of running as well as decrease the risk for injury. However, any deviation from preferred kinematics of gait has been show to increase the metabolic demands of the task.
PURPOSE: The purpose of this study was to examine the effect of altering running strike pattern on kinematic and metabolic parameters in healthy RF strike runners.
METHODS: Ten natural RF strike runners (5 males, 5 females, age = 25±5 yrs, mass = 64.74±9.55 kg) participated in this study. All subjects ran 27.2±7.1 km per week and were free of injury for at least 1 year. Subjects were asked to run on a treadmill at their preferred running speed (3.01±0.50 m/s) under two conditions: RF strike pattern and FF strike pattern. The order of conditions was counterbalanced. Oxygen consumption was measured with indirect calorimetry. Temporal-spatial parameters were collected for 60 s when the subject reached steady-state oxygen consumption. Differences between means were assessed by independent t-tests (alpha=0.05).
RESULTS: Switching to the non-preferred gait pattern did not significantly increase the steady state oxygen consumption during running. There was no difference in stride frequency within subjects.
CONCLUSIONS: There was no difference in steady state oxygen consumption when switching from a preferred to a non-preferred gait pattern in running. Therefore, recommending a runner to switch strike patterns may not provide a benefit in metabolic cost.