Plantar pressure and foot temperature responses to acute barefoot and shod running

Abstract

PurposeIncreased contact pressure and skin friction may lead to higher skin temperature. Here, we hypothesized a relationship between plantar pressure and foot temperature. To elicit different conditions of stress to the foot, participants performed running trials of barefoot and shod running.MethodsEighteen male recreational runners ran shod and barefoot at a self-selected speed for 15 min over different days. Before and immediately after running, plantar pressure during standing (via a pressure mapping system) and skin temperature (using thermography) were recorded.ResultsNo significant changes were found in plantar pressure after barefoot or shod conditions (<i>p</i> > 0.9). Shod running elicited higher temperatures in the forefoot (by 0.5-2.2°C or 0.1-1.2% compared with the whole foot, <i>p</i> < 0.01) and midfoot (by 0.9-2.4°C, <i>p</i> < 0.01). Barefoot running resulted in higher temperature variation in the rearfoot (0.1-10.4%, <i>p</i> = 0.04). Correlations between skin temperature and plantar pressure were not significant (<i>r</i> < 0.5 and <i>r</i> > -0.5, <i>p</i> > 0.05).ConclusionsThe increase in temperature after the shod condition was most likely the result of footwear insulation. However, variation of the temperature in the rearfoot was higher after barefoot running, possible due to a higher contact load. Changes in temperature could not predict changes in plantar pressure and vice-versa.