THE EFFECT OF REARFOOT MOTION ON ATTENUATION OF THE IMPULSE WAVE AT IMPACT DURING RUNNING

This study investigated whether rearfoot motion at heel contact during running attenuates the magnitude of the impact force traveling throug h the body. Fifteen subjects completed running trials for two conditio ns:(a) running on a treadmill at a self-selected speed and a cadence o f 160 steps/min and (b) running at the same speed and cadence but with rearfoot motion limited by a medial wedge inserted into the subject's shoe. A paired t test was used to test for differences between condit ions in the peak accelerations of each accelerometer and the time to p eak of the tibia acceleration. The predominant impact frequency and am plitude of the frequency peak were also tested for significant differe nces. No significant difference was found in the variables compared be tween the two conditions. The results demonstrated that restriction of rearfoot motion using a medial wedge during the initial 15% of the st ance phase has no effect on the characteristics of the impulse wave at the tibia.