Int J Sports Med 2016; 37(02): 154-158
DOI: 10.1055/s-0035-1559685
Orthopedics & Biomechanics
© Georg Thieme Verlag KG Stuttgart · New York

The Effects of a Transition to Minimalist Shoe Running on Intrinsic Foot Muscle Size

A. W. Johnson1, J. W. Myrer1, U. H. Mitchell1, I. Hunter2, S. T. Ridge1
  • 1Department of Exercise Sciences, Brigham Young University, Provo, United States
  • 2Exercise Sciences, Brigham Young University, Provo, United States
Further Information

Publication History

accepted after revision 27 July 2015

Publication Date:
28 October 2015 (eFirst)


A proposed benefit of minimalist shoe running is an increase in intrinsic foot muscle strength. This study examined change in intrinsic foot muscle size in runners transitioning to Vibram FiveFingers™ minimalist shoes compared to a control group running in traditional running shoes. We compare pre-transition size between runners who developed bone marrow edema to those who did not. 37 runners were randomly assigned to the Vibram FiveFingers™ group (n=18) or control group (n=19). Runners’ bone marrow edema and intrinsic foot muscle size were measured at baseline and after 10 weeks. Total running volume was maintained by all runners. A significant increase in abductor hallucis cross-sectional area of 10.6% occurred in the Vibram FiveFingers™ group compared to the control group (p=0.01). There was no significant change in any of the other muscles examined (p>0.05). 8 of the Vibram FiveFingers™ runners, and 1 control runner developed bone marrow edema. Those who developed bone marrow edema, primarily women, had significantly smaller size in all assessed muscles (p≤0.05). Size of intrinsic foot muscles appears to be important in safely transitioning to minimalist shoe running. Perhaps intrinsic foot muscle strengthening may benefit runners wanting to transition to minimalist shoes.