The human foot is a very complex structure, which allows it to serve many diverse functions. During standing, it provides our base of support. During gait, the foot must be stable at foot-strike and push-off. However, during mid-support, the foot must become a mobile adaptor and attenuate loads. It also possesses spring-like characteristics, storing and releasing elastic energy with each foot-strike. This is accomplished through the deformation of the arch, which is controlled by intrinsic and extrinsic foot muscles. There is evolutionary evidence that the foot arch architecture and musculature developed in response to the increased demands of load carriage and running. The stability of this arch, which we proposed to be the central ‘core’ of the foot, is requisite to normal foot function.

The relevance of Foot to core stability.
Core stability has received much attention in the clinical and athletic arenas. Interest has primarily been focused on the role of lumbopelvic-hip stability in normal lower extremity movement patterns. The muscular system of the lumbopelvic hip complex, or core, has been described as consisting of local stabilisers such as the multifidus and transverse abdominis, and global movers such as latissimus dorsi. The local stabilisers have small cross-sectional areas and small moment arms. Therefore, they do not produce large rotational moments at the respective joints that they cross. However, they do act to increase intersegmental stability. Proper function of local stabilisers provides a stable base on which the primary movers of the trunk, those with larger cross-sectional areas and moment arms, can act to cause gross motion. When core muscles are weak or are not recruited appropriately, the proximal foundation becomes unstable and malaligned, and abnormal movement patterns of the trunk and lower extremity ensue. This can lead to a variety of overuse lower extremity injuries. This is where the ” short foot ” exercise comes into play  .

The short foot exercise can be viewed as a foundational exercise for foot and ankle rehabilitation as well and for Core strengthening.