Footwear Innovation Science & Research: Aspects of Data Collection Methodology, Sub-Group Requirements and Functional Threshold Implications

Running shoes are the main interface between the athlete and the road. Since the 1980’s significant effort has been put into understanding running mechanics and the influence a shoe can have on performance, incidence of injury and comfort. However, there is limited knowledge on whether the predominant research methodology is useful in analyzing an activity that is mainly characterized by continuous motion. In addition, the majority of research has been conducted on Western runners, with little knowledge on whether previous findings can be related to runners of different ethnicity. Finally, when assessing the influence of running shoes on objective running biomechanics and subjective perception, the majority of studies have used shoes outside the commercial market range. This makes it difficult to know the minimum requirements to trigger changes in biomechanics and perception. The first study investigated running biomechanics and running shoe characterization during discontinuous runway running along a 20 m runway and continuous loop running around a 140 m concrete running loop in three different shoe conditions. It was found that running mode influenced running biomechanics, with reductions seen in ground contact time and peak braking force during continuous loop running. Furthermore, continuous loop running induced a flatter and more inverted foot-strike at touchdown, shown by a reduced sagittal plane shoe-ground angle and increased ankle inversion angle. Shoe classification remained similar across the two modes, with similar kinetic and kinematic effects seen in both discontinuous runway running and continuous loop running. The findings indicate that when precise variable magnitudes are required continuous loop running should be used but discontinuous runway running is sufficient for comparative shoe functionality evaluations. The second study assessed the running biomechanics and perception of Chinese men and women. The results showed differences in running mechanics, with females exhibiting increased hip internal rotation, knee flexion and abduction, as well as reduced sagittal plane shoe-ground angle and ankle inversion at touchdown in comparison to Chinese male runners. Females also exhibited increased maximal and mean vertical loading rates in comparison to their male counterparts. Despite the differences in loading, females did not perceive shoe cushioning to be worse than males. Differences between Chinese men and women followed similar trends to that of Western men and women, with Chinese females showing increased joint ranges of motion. This indicates that shoe design should focus on creating a shoe which provides gender specific performance and comfort. The third study examined the influence of mechanically different midsole hardness’s that are within a commercial range on running biomechanics and subjective perception. The findings showed no differences in lower limb kinematics. Softer shoes reduced the maximal vertical loading rate in comparison to a medium and harder shoe. Subjectively, runners were able to perceive a difference between the softer and harder shoe models. This suggests that a smaller difference in material hardness is required to elicit differences in biomechanical loading than is required to trigger differences in subjective perception. This thesis has revealed that there are differences in running biomechanics depending on the methodology used as well as providing knowledge on an under researched population. It has also provided information regarding a minimum threshold required to trigger differences in running biomechanics and subjective perception. Findings will benefit the running shoe industry by providing a methodology which can improve shoe design, and thresholds which can improve the manufacturing process of running shoes.