Human Locomotion

Taddei U, Matias A, Duarte M, Sacco I. Foot core training to prevent running-related injuries: a survival analysis of a single-blind, randomized controlled trial. Am J Sports Med 2020; 48:3610-3619.

Monthly Research Articles

In any given year, nearly 80% of long-distance runners are injured. The authors of this study point out that to date, no satisfactory treatment has ever been developed to prevent running-related injuries. To that end, the authors set out to determine if foot strengthening exercises could reduce the rate of running-related injuries in recreational long-distance runners over the course of 1 year. 118 runners were recruited with 57 of them being placed in an intervention group incorporating specific foot/ankle exercises, and a control group of 61 people.

At the start of the study, the authors evaluated each participant’s arch height, foot strength, body mass, foot strike pattern, shoe gear, previous injury, running volume and running pace. The runners were reevaluated at eight weeks and sixteen weeks and a weekly report was kept on the participant’s running distance, pace, and injuries for 12 months. Foot strength was measured by having the subjects press their toes against a pressure platform, which is similar to the toe strength dynamometer used on our site.

At the end of the study, the authors found no correlation between running-related injuries and shoe use, arch height, BMI, foot strike pattern, sex, years of practice, weekly mileage, and/or running pace. The single best predictor of noninjury during this study was foot strength at the start of the study. In fact, the authors state “The stronger the foot, the longer it took the runner to develop a running-related injury.” The authors also make the significant observation that as the runners increased their toe strength, their potential for injury went down, but it took time for the strength gains to take effect. After 4 months of foot strengthening, the reduced injury rates became apparent, but it took a full 8 months for a statistically significant drop in injury rates to occur. By the end of the study, those placed in the control group who did not do foot strengthening exercises were 2.42 times more likely to be injured. The authors theorized that strengthening the arch allows for improved shock absorption and better transfer of forces during propulsion.

These authors have published previously on the effect of foot strengthening programs in runners. In a 2020 paper published in Physical Therapy in Sport, the authors prove that an 8-week foot strengthening program increased thickness of the abductor hallucis muscle, resulting in an increase in propulsive forces in recreational runners. The authors claim this could improve running performance and site additional references showing how foot strengthening exercises can improve horizontal jump distance, reduce the degree of bunion formation, increase arch height, alter the center of pressure displacement while balancing, and reduce a seniors risk of falling by a factor of 7.

While the authors of this study used an expensive force platform to measure toe strength, it is possible to get the same measurements using the toe strength dynamometer available on the site. Researchers from University of Virginia recently showed this device has an interrater reliability of .95. Additionally, unpublished data from Temple University proves that 6 weeks of doing ToePro exercises results in a 30% increase in toe strength along with improved balance as measured with the anterior reach test. While a growing body of research shows a strong connection between toe strength and performance, especially horizontal jump distance, this is just one more paper that shows a powerful connection between running-related injuries and foot strength.