The variable nature of motor patterns and the potential for a change in substrate or speed with each step imply that each pressure record will be slightly different . A recent study of plantar pressure at a single walking speed using approximately 500 records per subject, demonstrated large inter- and intra-subject (i.e. step-to-step) pressure variation in the midfoot . However, discussion of variability across the whole plantar surface and the influence of speed were not considered as part of that contribution.