Abstract
This study investigated the consistency and validity of a new measurement method to determine the support time in the contact phase during running using a digital voice recorder (sampling frequency 44,100Hz). Fifteen male trained runners participated in this study, and they performed 50% effort running in a facility. We analyzed the force plate system and 2 kinds of measurement methods (Exp.1 and Exp.2 were applicated a piezoelectric element and a microphone, respectively) for measuring support time during running. We compared the results between the force plate system and 2 measurement methods using Bland-Altman analysis and Intraclass correlation coefficient (ICC). In the Exp.1, Fz pi and Vpi support time were 147.37 ± 12.28 ms and 139.41 ± 18.75 ms, respectively. The ICCpi (2,1) was 0.725 (ranging from 0.583 to 0.819). In the Exp.2, Fz mic and Vmic support time were 161.00 ± 11.36 ms and 167.99 ± 12.51 ms, respectively. The ICCmic (2,1) was 0.836 (ranging from -0.035 to 0.964). These results indicated that observed values of Exp.2 were more correctly than those of Exp.1, suggesting that the footstep measurement method could be available to determine support time during running.
