Soccer shoe bending stiffness significantly alters game-specific physiology in a 25-minute continuous field-based protocol

Abstract

The purpose of this study was to investigate the effects of soccer shoes with differing bending stiffness on physiological and performance variables in a game-like situation. A sample of 13 male soccer players was recruited to complete this study. Three soccer shoes with different forefoot bending stiffness (low, medium, high) were compared using a continuous field-based work protocol (the Soccer-25). Participants performed the Soccer-25 while the physiological (rate of oxygen consumption, heart rate, ventilation, and rate of energy expenditure) and performance variables (drill completion times) were recorded. The Soccer-25 consists of seven phases, Drills 1–3 and Shuttle Runs 1–4. A one-way repeated measures ANOVA was used to determine whether there were any significant effects for soccer shoe condition for each of the physiological and performance variables. The medium-stiffness shoe was significantly lower than the high-stiffness shoe for a number of physiological variables, including global oxygen consumption (p = 0.044), heart rate during Drills 2 (p = 0.043), ventilation during Shuttle Run 4 (p = 0.016), global energy expenditure (p = 0.043), and rate of energy expenditure during Drills 1 (p = 0.044). The low stiffness shoe was not significantly different from the medium- or high-stiffness shoes. No significant differences were found for any of the performance variables. Soccer shoe forefoot bending stiffness significantly affects the physiological variables in a game-like situation.