FRONTAL REARFOOT KINEMATICS IN RUNNING PRIOR TO VOLITIONAL EXHAUSTION

Excessive rearfoot motion, especially in the frontal plane, is believe d to be a major cause of overload injuries in running. The aim of this study was to determine the influence of fatigue on frontal rearfoot m otion just before volitional abandonment during an exhaustive run on a treadmill. Rearfoot kinematics were recorded three-dimensionally and reconstructed in a frontal plane associated with the heel. Statistical analysis of the results suggested that exhaustion did not influence t ibial varum substantially, except at first heel strike. However, maxim al calcaneal eversion and subtalar pronation did increase significantl y, while maximal pronation velocity accelerated to 100% more than at t he start of the exhaustive run. Also, the results of this study sugges t that the increase in rearfoot motion is directly affected by fatigue and not by a fatigue-induced increase in step length.