Running Velocity as a Methodological Factor in Footwear Testing: Fixed Versus Self-Selected Conditions

Running velocity is an important methodological factor in footwear research, given its potential influence on biomechanical parameters used to evaluate shoe-specific effects. Since most previous studies have assessed footwear effects at standardized running velocities, it remains unclear whether shoe-specific biomechanical response patterns differ when runners transition to individually selected faster outdoor running velocities. Therefore, this study examined whether footwear-related biomechanical responses were modified by running velocity. Twenty-two runners completed outdoor running trials at two running velocities in seven running shoes differing in cushioning and midsole bending stiffness. Four commonly used inertial measurement unit-derived biomechanical parameters were assessed to determine whether shoe-specific responses differed between the two velocity conditions. Across all parameters, no significant shoe condition × running velocity interaction effects were observed. Higher running velocities increased the magnitude of the measured parameters, while the tested interaction terms did not provide statistical evidence that the relative shoe-related response patterns were systematically altered within the investigated velocity range. These findings suggest that individually preferred running velocities may be suitable for comparing relative shoe effects in field-based footwear testing for the investigated parameters and velocity range.