Does size matter? The influence of shoe-hole sizes on foot-mounted marker motion during walking gait

Background To quantify in-shoe foot kinematics, studies have relied on cutting holes in the shoe upper to allow markers to be placed on the foot. Although previous research has suggested optimum hole sizes to preserve the structural integrity of the shoe [1], there is no empirical basis for what size holes are required to allow free-motion of individual markers during gait. The aim of this study was to determine the effect of different diameter holes on skinmounted marker motion during walking in athletic footwear. Methods Eighteen healthy adults participated in this study (10M:8F, mean age 22.7 years SD 3.7, height 1.74 m SD 0.08, body mass 71.2 kg SD 8.5). Wand-mounted surface markers were attached directly to the foot [2] or directly to the foot for barefoot measurements, which were used as a reference for comparisons. Each participant performed five walking trials in athletic footwear (ASICS Gel-Pulse 3). Three sets of identical shoes were used with holes of 15 mm (A), 20 mm (B) and 25 mm (C). All conditions were tested in a random order. Marker