Relationships between Foot Morphology and Foot Muscle Strength in Healthy Adults

Abstract

The purpose of this study was to investigate if measurements of foot morphology in sitting and standing positions can predict foot muscle strength. Twenty-six healthy male adults were recruited, and their foot morphology and foot muscle strength were measured. Foot morphological variables, toe flexor strength, and metatarsophalangeal joint flexor strength were measured by using a digital caliper, Ailitech-AFG500 dynameter and metatarsophalangeal joint flexor strength tester, respectively. Partial correlation and multivariate stepwise regression were used to explore the relationships between foot morphology and toe/metatarsophalangeal joint strength. Results adjusted by age and body mass index were as follows: (1) truncated foot length in sitting and standing positions and foot width in standing position were positively correlated with the flexor strength of the first toe; (2) foot length, foot width, and truncated foot length in both positions were positively related to the flexor strength of the other toes; (3) arch height index in sitting position and differences in navicular height were negatively associated with the flexor strength of the other toes; (4) differences in foot width were negatively associated with metatarsophalangeal joint flexor strength; and (5) the multivariate stepwise regression model showed that truncated foot length in sitting position, navicular height in standing position, differences in navicular height, foot width in sitting position, and differences in foot width were significantly correlated with toe/metatarsophalangeal joint flexor strength. Simple measurements of foot morphological characteristics can effectively predict foot muscle strength. Preliminary findings provided practical implications for the improvement of the foot ability by making specific foot muscle training sessions in professional sports and by compensating the predicted muscle strength defects to prevent foot injury.

Effects of a 12-week gait retraining program combined with foot core exercise on morphology, muscle strength, and kinematics of the arch: A randomized controlled trial

“…Moreover, the improvement reached a moderate effect size (Cohen’s d = 0.55), which was superior to previous studies with no significant changes in arch height after standalone interventions ( Lynn et al, 2012 ; Miller et al, 2014 ). Some researchers pointed out that the function of the foot intrinsic muscles is directly related to the structure of the longitudinal arch ( Fiolkowski et al, 2003 ; Soysa et al, 2012 ; Kelly et al, 2014 ; Xiao et al, 2020 ). For example, to prevent the occurrence of excessive arch deformation, the recruitment of foot muscles increases with external increasing load when a decrease in electromyographic activity of these muscles leads to an increase in the navicular drop, thus revealing the relationship between the lower extremity loading and the foot muscles activation levels ( Fiolkowski et al, 2003 ; Kelly et al, 2014 ).…”

Acute Effects of High-Definition Transcranial Direct Current Stimulation on Foot Muscle Strength, Passive Ankle Kinesthesia, and Static Balance: A Pilot Study

“…MPJ flexor strength was measured using an MPJ flexor strength testing system customized by our team. The validity and reliability were reported previously [29,30]. Each participant was seated in the system with bare feet and legs.…”