Influence of shoe stack height on patellofemoral kinetics and joint work during running

Abstract Footwear companies modify midsole stack height in running shoes, often aiming to either enhance performance or reduce the risk of injuries, such as patellofemoral pain. Despite changes in midsole characteristics, the incidence of running-related injuries remains high. Limited research has investigated the effects of minimal, traditional, and maximal footwear in the same study. Therefore, the purpose of this study was to compare patellofemoral kinetics and ankle, knee, and hip joint work between minimal, traditional, and maximal footwear during running. It was hypothesised that minimal shoes would reduce patellofemoral joint stress and knee negative work but increase ankle negative work compared to traditional and maximal shoes. Twenty-seven healthy runners completed five trials in each footwear condition, while an 8-camera motion capture system and two embedded force plates collected three-dimensional kinematic and kinetic data of the hip, knee, and ankle. Peak quadriceps force, patellofemoral joint reaction force, patellofemoral joint stress, and positive, negative, and net joint work were compared between footwear conditions using repeated measures ANOVAs (α = 0.05). Peak quadriceps force, patellofemoral joint reaction force and patellofemoral joint stress were significantly lower in the minimal shoe compared to the maximal and traditional shoes. Negative ankle work was significantly higher in the minimal shoe and significantly lower in the maximal shoe compared to the traditional shoe, while net ankle work was significantly lower in the minimal shoe compared to the maximal and traditional shoes. Negative knee work, positive knee work, and net knee work were significantly lower in the minimal shoe compared to the other two shoes. These findings suggest that midsole stack height can influence patellofemoral kinetics as well as joint work at the ankle and knee.