Author(s): IRIGUCHI, K., NOZU, S., TOGASHI, I., AOYAGI, M., UCHINO, S., TAKAZAWA, Y., Institution: JUTENDO UNVERSITY, Country: JAPAN, Abstract-ID: 1792

INTRODUCTION:
The incidence of running-related injuries has been reported to be 18.3% in males and 25.9% in females among collegiate long-distance runners. Foot arch morphology and vertical ground reaction force (vGRF) at foot contact during running have been suggested as contributing factors to running-related injuries, as both may adversely affect lower-limb kinematics. Previous studies have reported sex-related differences in foot arch morphology, which may influence vGRF at foot contact and potentially contribute to sex differences in the incidence of running-related injuries. Therefore, the purpose of this study was to examine the relationship between foot arch morphology and vGRF during running between males and females.
METHODS:
Thirty-nine collegiate long-distance runners (21 males and 18 females) participated in this study. age, height, and body mass were 19.6 ± 1.2 years, 167.9 ± 5.0 cm, and 55.0 ± 5.8 kg for males, and 19.8 ± 1.3 years, 161.8 ± 4.1 cm, and 50.8 ± 4.4 kg for females, respectively. Foot arch morphology was assessed using the Arch Height Index (AHI), calculated as the dorsum height at 50% of foot length in a seated position divided by the foot length from the heel to the first metatarsophalangeal joint. vGRF during running was measured using a force plate while participants ran at a speed of 18 km/h. vGRF data were sampled at 1000 Hz, filtered using a low-pass filter with a cutoff frequency of 35 Hz, and normalized to body weight. Outcome variables included the initial peak, maximum peak, impulse, VILR, and VALR. An independent t-test was used to examine sex differences in AHI. Analysis of covariance (ANCOVA) was conducted with each vGRF variable as the dependent variable, sex as the fixed factor, and AHI as the covariate. When a significant interaction was observed, simple linear regression analyses were performed separately for each sex.
RESULTS:
No significant sex difference was observed in AHI (p = 0.89). No significant main effect of sex was found for any vGRF variables. However, significant sex-by-AHI interactions were observed for VILR (F = 6.67, partial η² = 0.28, p < 0.01) and VALR (F = 6.71, partial η²= 0.28, p < 0.01). Simple linear regression analyses revealed significant associations between AHI and both VILR and VALR in males (VILR: B = 918.21, β = 0.60, R² = 0.38, p < 0.01; VALR: B = 1178.31, β = 0.62, R² = 0.39, p < 0.01), whereas no significant associations were found in females (VILR: p = 0.72; VALR: p = 0.97).
CONCLUSION:
The relationships between foot arch morphology and both VILR and VALR differ between male and female collegiate long-distance runners.