The influence of walking speed and heel height on peak plantar pressure in the forefoot of healthy adults: a pilot study

Background: The body of empirical research is suggestive of the fact that faster walking speed and increasing heel height can both give rise to elevated plantar pressures. However, there is little evidence of the interaction between walking speed and heel height on changes in plantar pressure. Therefore, the aim of this study was to investigate whether the effect of heel height on plantar pressure is the same for different walking speeds. Methodology: Eighteen healthy adults, between the ages of 18 and 35 were assessed for changes in peak plantar pressure at walking speeds of 0.5 mph, 0.8 mph, 1.4 mph and 2.4 mph on a treadmill, wearing heels of 2 cm, 3 cm, 6 cm and 9 cm. Both the speed of walking and heels were randomly assigned to each participant. Peak plantar pressure values were determined in the forefoot region using the F-scan system which made use of in-shoe insoles. Data were analysed using two-way ANOVA. Results: Increasing heel height and walking speed resulted in significantly higher peak plantar pressure in the forefoot. Post-hoc analysis also confirmed the findings of two-way ANOVA of significant increase in peak plantar pressure with increments in heel height and walking speed. The two-way ANOVA illustrated significantly higher peak plantar pressures in both the forefeet due to interaction of walking speed and increasing heel heights. Conclusion: This study suggests that an interaction of walking speed and footwear design on distribution of plantar pressure exists. Therefore it is necessary to standardize walking speed and shoe design in future studies evaluating plantar pressures.