Investigation of the Ground Reaction Force Parameters According to the Shoe's heel Heights and Landing Distance during Downward Stairs on Bus

Abstract

The purpose of this study was to investigate the GRF(ground reaction force) parameters according to the shoes's heel heights and ground landing distances during downward stairs on bus. Participants selected as subject were consisted of young and healthy women(n=9, mean age: 21.30±0.48 yrs, mean height: 164.00±3.05 cm, mean body mass: 55.04±4.41 kg, mean BMI: 20.47±1.76 kg/m2, mean foot length: 238.00±5.37 mm). They were divided into 2-types of shoe's heel heights(0 cm/bare foot, 9 cm) and also were divides into downward stairs with 3 types of landing distance(20 cm, 35 cm, 50 cm). A one force-plate was used to collect the GRF(AMTI, USA) data from the sampling rate of 1000 Hz. The GRF parameters analyzed were consisted of the mediallateral GRF, anterior-posterior GRF, vertical GRF, loading rate, Center of Pressure(ΔCOPx, ΔCOPy, COP area) and Dynamic Postural Stability Index(MLSI, APSI, VSI, DPSI) during downward stairs on bus. Medial-lateral GRF and vertical GRF didn't show significant differences statistically according to the shoe's heel heights and landing distance, but 9 cm shoes heel showed higher vertical GRF than that of 0 cm bare foot in landing distance of 50 cm. Also anterior-posterior GRF didn't show significant difference statistically according to the shoe's heel heights, but landing distance of 20 cm showed higher than that of landing distances of 35 cm and 50 cm in anterior-posterior GRF. Loading rate didn't show significant difference statistically according to the landing distance, but 9 cm shoe's heel showed higher than that of 0 cm bare foot during downward stairs. The ΔCOPy and COP area didn't show significant differences statistically according to the shoe's heel heights and landing distance, but 0 cm bare foot showed higher than that of 9 cm shoe's heel in ΔCOPx. Dynamic Postural Stability Index(MLSI, APSI, VSI, DPSI) didn't show significant differences statistically according to the landing distance, but 9 cm shoe's heel showed decreased value than that of 0 cm bare foot in dynamics balance. Considering the above, parameters of GRF showed different characteristics according to the shoe's heel heights and ground landing distances during downward stairs on bus.

Effect on the parameters of the high-heel shoe and transfer time of ground reaction force during level walking

“…But in case of wearing high heel shoe, excessive impact on ankle due to cognition error of exact touch-down distance to ground at heel touch-down by hyper-plantar flexion of ankle joint can be generated (Hyun and Ryew, 2014c). …”

“…That is, higher heel height, the more function of cognitive sensory of vertical height at touch-down of next 1 step can be deteriorated (Hyun and Ryew, 2014c). …”

Effects of Fatigue Induction on Ground Reaction Force Components, Postural Stability, and Vertical Jump Performance in Taekwondo Athletes

“…Static postural stability was measured by taking the integral of the anteroposterior (AP) center of pressure (COP), mediolateral (ML) COP (Michell, Ross, Blackburn, Hirth, & Guskiewicz, 2006) and the maximal and minimal changes created by the path of the COP (Hyun & Ryew, 2014).…”

“…Therefore, we assessed precision based on the period from the moment the right foot contacts the ground until the point at which the first peak vertical force (PVF) is created (Hyun & Ryew, 2014). Higher values for each direction indicate lower stability, while lower values indicate higher stability.…”

Effects of Vertical Jump Performance and Ground Reaction Force Variables according to the Fatigue by Submaximal Treadmill Exercise

“…         Figure 3. Vertical jump according to the fatigue (Wikstrom et al, 2005) 최대 값(max) 발생시점을 기준 으로 평가하였다 (Hyun & Ryew, 2014).…”