Intrinsic foot muscles(IFM) are the prime stabilizers of the foot. When the IFM become weakened and unstable, the foot and lower limb become more vulnerable to injury. IFM develop across early childhood and evidence suggests that the critical time window for foot arch development is the first 6 years of life (i.e., preschool age). Human's feet and arches developed naturally due to the daily loads imposed on them, while evidence for using protective footwear to promote arch development is very weak. Moreover, the investigation suggested that local children may have a danger in insufficient daily physical activity. Thus the children may be at high risk for having weak feet.~Minimalist shoes are defined as footwear with little to no cushioning, highly flexible soles, and no arch support devices. Minimalist shoes are shaped with a wide toe box, allowing the foot to move more naturally than when confined in conventional footwear. Both running and walking studies have shown that the use of minimalist shoes increases IFM strength by increasing the mechanical load to the foot. Measuring the strength of individual IFM is challenging at best. However, muscle strength has been directly correlated with muscle size. As a result, studies have used imaging techniques such as MRI and ultrasound to measure foot muscle size. A very recent study suggests that walking with minimalist shoes increased the cross-sectional area (CSA), thickness and strength of IFM in adults. Similar findings have been reported by another study adopting a 12-week program.~This study aims to investigate the effects of a 12-week in-school walking training with minimalist shoes for local preschool children on intrinsic foot muscle size, muscle strength, and foot arch stiffness.~In view of the treatment effectiveness and user-friendliness, walking with minimalist shoes may impose a positive impact to strengthen the IFM and promote foot arch stiffness for preschool children.
This is a single-blind randomized control study that will investigate the effects of a 12-week in-school walking training with minimalist shoes for local preschool children on intrinsic foot muscle size, muscle strength, and foot arch stiffness. The children in the control group will wear traditional footwear with arch support. It is hypothesized that walking with minimalist shoes may impose a positive impact to strengthen the IFM and promote foot arch stiffness for preschool children.