Summary
The human foot is specialized for bipedal locomotion and relies on a deformable arch whose stiffness is regulated by intrinsic foot muscles. These muscles are essential for normal foot function. This study tested whether regular daily activity in minimal footwear, which provides little structural support, increases foot muscle strength. Western adults wore minimal footwear during normal daily activities for six months. Foot strength, defined as maximal isometric plantarflexion strength at the metatarsophalangeal joints, and foot biometrics were measured before and after the intervention. A second group with an average of 2.5 years of minimal footwear experience was also assessed to examine long-term effects.
After six months, foot strength increased by an average of 57.4% (p < 0.001). The experienced group showed similar strength levels to the post-intervention group, indicating that approximately six months of regular minimal footwear use is sufficient to achieve maximal strength gains. These improvements in intrinsic foot muscle strength may support better balance and gait.
PMID: 34545114
PMCID: PMC8452613
DOI: 10.1038/s41598-021-98070-0
Abstract
The human foot is uniquely adapted to bipedal locomotion and has a deformable arch of variable stiffness. Intrinsic foot muscles regulate arch deformation, making them important for foot function. In this study we explore the hypothesis that normal daily activity in minimal footwear, which provides little or no support, increases foot muscle strength. Western adults wore minimal footwear for a six-month period (the “intervention” group). Foot strength, i.e., maximum isometric plantarflexion strength at the metatarsophalangeal joints, and foot biometrics were measured before and after the intervention. An additional group was investigated to add further insight on the long-term effects of footwear, consisting of Western adults with an average 2.5 years of experience in minimal footwear (the “experienced” group). This study shows that foot strength increases by, on average, 57.4% (p < 0.001) after six months of daily activity in minimal footwear. The experienced group had similar foot strength as the post intervention group, suggesting that six months of regular minimal footwear use is sufficient to gain full strength, which may aid healthy balance and gait.
Curtis R, Willems C, Paoletti P, D'Août K. Daily activity in minimal footwear increases foot strength. Sci Rep. 2021 Sep 20;11(1):18648. doi: 10.1038/s41598-021-98070-0. PMID: 34545114; PMCID: PMC8452613.