E-29 Free Communication/Poster - Foot and Ankle Mechanics Friday, June 3, 2016, 7: 30 AM - 12: 30 PM Room: Exhibit Hall A/B
The medial longitudinal arch has been classified as the central core of the foot. Its structure and integrity during running largely depend on the strength and function of intrinsic and extrinsic foot muscles.
PURPOSE: To observe strength and size changes in intrinsic foot muscles (IFM) between a foot strengthening exercise group (FS), a group walking in minimalist shoes (MSW) and a control group (C).
METHODS: 22 healthy college subjects (age 22.6±2.5 years, height 174.2±10.8 cm, weight 68.3±12.6 kg) were recruited and randomly assigned to either the FS, MSW, or C and monitored over 8 weeks. The FS followed a series of progressive exercises designed to target IFM while the MSW began walking 2,500 steps daily reaching 7,000 steps daily by the end of the study. All groups maintained consistent running mileage. Strength testing was completed at week 0 and 8 using a customized dynamometer for doming, great toe flexion and lateral toe flexion. Ultrasound images were recorded at week 0 and 8 of the abductor hallucis (ABDH), quadratus plantae (QP), flexor digitorum brevis (FDB) and flexor hallucis brevis (FHB). Measurements included the cross-sectional areas (CSA) of the ABDH, QP, FDB and thickness of the FHB. Data were analyzed using an ANCOVA with a post-hoc test to determine differences in size and strength within the groups.
RESULTS: See table below for specific results.
Discussion: The preliminary data suggest that increasing IFM size and strength can be done by following an exercise protocol. IFM strength can also occur while walking in minimalist shoes. Increases in doming strength among all groups may be due to a potential learning curve.