Change of the foot morphology after long-distance running

When a trained runner goes out running, he puts his shoes on, laces them and starts his running session. Lacing your shoes is an automatism that you learn to do as a child. You lace them tightly according to the shape of the foot for running. But a foot is not a fixed object and changes. Are these changes to the foot when running significant and do they have implications for the fit?

A study by Mako Funako and Shigeo Iso in 2016 shows that the shape does actually change. They carried out a study with 21 male, trained, healthy runners who ran a distance of 35 km. A 3D scan was taken before and after the running session. A comparative study was made of the morphology of the foot. A signification reduction was found here of the dorsal height, navicular height and foot volume. The arch height ratio was lower after running, with no visible change in the foot length. This may be due to neuromuscular changes of extrinsic and intrinsic foot muscles and a change in the mechanical properties of soft tissue in the foot.

This change may influence the fit and/or comfort of the shoe when running. If the shoe does not fit correctly, it may result in blisters and bruising. So an experienced runner who previously had no foot problems may still develop problems after long-distance running. Sometimes retying the shoe laces after a number of kilometres is sufficient to prevent further problems. As the shoe must fit perfectly to achieve the optimum performance.

Fukano, M., & Iso, S. (2016). Changes in foot shape after long-distance running. Journal of Functional Morphology and Kinesiology, 1(1), 30-38.