Modification of the foot posture index in neutral and pronged feet under the effect of fatigue

Abstract

Objective: To analyse the modification of the Foot Posture Index a stressful situation for the musculature of the lower limb and to value the capacity of recuperation after a period of rest. Method: The Foot Posture Index was determined (FPI-6) in 63 healthy adult subjects and they were tested with "continuous counter-movement jumps (CMJ) conducted for 30 seconds". Each subject's FPI-6 was then valued, and again after 15 minutes rest. Results: There were statistically significant changes in the foot posture in both groups when relating the three experimental situations (before and immediately after the test and after the rest). These changes present a strong effect between the basal and post moments, and between the post and rest moments. After the test, there is an increase of the FPI-6 value with respect to the initial situation. After the rest, the changes observed were significant in relation to those obtained after the test with a decrease of the FPI-6 values, although they did not return to the initial values prior to the test. Conclusions: The fatigue produced by the continuous counter-movement jumps (CMJ) conducted for 30 seconds affects the FPI values, increasing them, but this is not sufficient to modify the foot posture classification in the groups of neutral and pronated feet studied. The time of rest proposed was not enough to return to the initial situation.