The Short-Foot Exercise and Dynamic Balance

Study Title: Differences in Static and Dynamic Balance Task Performance After 4 Weeks of Intrinsic Foot Muscle Training: The Short-Foot Exercise Versus the Towel-Curl Exercise
Authors: S. Lynn, R. Padilla & K. Tsang
Journal: Journal of Sport Rehabilitation
Date: 2012
.
Summary:

• This study, from Cal State-Fullerton, compared the effects of towel curls and the short-foot exercise on static and dynamic single-leg balance tasks. Towel curls have traditionally been used for foot muscle strengthening however, such exercises theoretically may actually recruit more of the extrinsic foot musculature rather than the intrinsics.
• A RCT was used in this study whereby 30 healthy university students (24 completed the study) were assigned to either the short-foot exercise group, the towel-curl exercise group or a control group. The dependent variables of the study were range of mediolateral movement of the center of pressure during static and dynamic balance tests and standing navicular height. The center of pressure was measured via forceplate while performing a modified Y-balance test (without the test device).
• The participants performing the short foot exercise were instructed to raise the medial longitudinal arch by drawing in the metatarsal heads toward the calcaneus without flexing the toes and holding this position for 5 seconds each repetition. The participants performing the towel curl exercise were instructed to drag a towel (placed on a slick surface) under their foot via toe flexion to generate a strong grip for 5 seconds per repetition. Each group performed 100 repetitions daily for 4 weeks, progressing from seated to standing positions.
• During the static tasks, no differences were found. During the dynamic balance test, both intervention groups demonstrated a significant decrease in movement of the COP of both the dominant and non-dominant limbs however, the short foot group demonstrated much greater improvement (an average decrease by 9.3 mm). This was a large effect size.
• To me, this paper wasn't very impressive. It seemed like a mountain was made out of a molehill with their results. I do prefer the short foot exercise over the towel curl exercise but I generally use an integrated approach as demonstrated in this post. I do understand that variables need to be isolated for the purposes of research, but a static hold and dynamic contractions to me are quite different.

.
Lynn, SK., Padilla, RA., & Tsang, KW. (2012). Differences in static- and dynamic-balance task performance after 4 weeks of intrinsic-foot-muscle training: The short-foot exercise versus the towel-curl exercise. Journal of Sport Rehabilitation, vol 21; 327-333

​