Do maximalist shoes mitigate risk factors for tibial stress fractures better than stability or flexible (marketed as minimalist) shoes?

Abstract

Background: Tibial stress fractures (TSF) are a common running related injury. Specific risk factors include increased rearfoot eversion and increased vertical instantaneous and average loading rates (VILR and VALR, respectively). Since these risk factors are mechanical in nature, certain types of running shoes may be able to reduce these risk factors for TSF. The objective of this study was to determine the effects of maximalist, stability, and flexible (commercially marketed as minimalist) running shoes on specific risk factors for TSF in male and female runners.Methods: Fourteen recreation runners were recruited for this study, 7 males and 7 females. A 14-camera motion capture system and three force plates were used to capture each subject’s kinematics and kinetics. Subjects ran in maximalist (Hoka Bondi 5), stability (Nike Structures), neutral (Nike Pegasus), and flexible (Nike Free) shoes.Results: Among males there was a significant increase in ankle internal rotation ROM in the maximalist shoe compared to neutral. There was also a significant decrease in ankle internal rotation ROM in the flexible shoe compared to neutral. Among females there was a significant reduction in peak ankle eversion and ankle eversion ROM.Conclusions: The results of this study suggest that the maximalist shoes may reduce the pronation component of TSF risk factors in female runners. The maximalist shoes were able to reduce the peak ankle eversion and ROM. This is likely due to the specific design mechanism of the maximalist shoe to control foot motion.