Investigation into the kinetics and kinematics during running in the heelless shoe

Background: Recent evidence suggests that runners who habitually rearfoot strike suffer higher rates of chronic injuries compared to those who adopt a mid/forefoot strike pattern. Based on this information new experimental heelless footwear was developed with the aim of mediating a mid/forefoot strike pattern.Objectives: The aim of the current investigation was to examine the three-dimensional (3D) kinematics and ground reaction forces (GRFs) of running in conventional footwear in comparison to the heelless shoes.Methods: Twelve male participants ran at 4.0 m.s−1±5% in each footwear condition. Angular joint kinematics from the hip, knee and ankle in the sagittal, coronal and transverse planes were measured using an eight-camera optoelectric motion capture system. Synchronous ground reaction forces were also obtained allowing impact load parameters and estimates of Achilles tendon force to be quantified. Differences in GRFs and 3D kinematics between footwear were assessed using paired t-tests.Results: The kinematic analysis indicated that, in comparison to the conventional running footwear, the heelless shoes were associated with significantly greater plantarflexion at foot strike and peak ankle eversion angle. Furthermore, the GRF analysis revealed that, compared to the conventional footwear, impact parameters were significantly lower in the heelless footwear.Conclusions: Given the reduction in impact loading rates and increases in ankle eversion that were observed in heelless footwear, running in this type of footwear may reduce the incidence of chronic injuries linked to excessive impact forces. However, it may increase the injury potential that is associated with excessive ankle eversion.