Medial Longitudinal Arch Mechanics Before and After a 45 Minute Run

Abstract BACKGROUND:Medial longitudinal arch integrity following prolonged running has yet to be well documented. Our purpose was to quantify changes in medial longitudinal arch kinematics before and after a 45 minute run in healthy recreational runners. METHODS:Thirty runners performed barefoot seated, standing, and running trials before and after a 45 minute shod treadmill run. Navicular displacement, arch lengthening, and arch height index were used to quantify arch deformation, and arch rigidity index was used to quantify arch stiffness. RESULTS:There was no statistical difference in navicular displacement (mean (95% CI): 5.6 (4.7-6.4)), arch lengthening (3.2 (2.6-3.9)), change in arch height index (0.015 (0.012-0.018)), or arch rigidity index (0.95 (0.94-0.96)) after the 45 minute run (all MANOVA P{greater than or equal to}0.065). CONCLUSIONS:Since there was no statistically significant change in arch deformation or rigidity, either the structures of a healthy, intact medial longitudinal arch are capable of adapting to cyclical loading or they are capable of withstanding a 45 minute run without compromise.