A recent study compared the use of +20 mm, +40 mm, and +60 mm pedal spacers in terms of cycling efficiency and biomechanical outcomes. Efficiency was higher when no spacer was used without any differences in terms of movement patterns (i.e. kinematics) or muscle activity. This result align with prior research that demonstrated that a narrow distance between pedals (i.e. Q-factor) improves cycling efficiency. The rationale for this improvement in function still needs further investigation though potentially looking at pedal and muscle forces, which have not been explored in prior studies. It may be the case that, with a narrow spacer, hip abductors (e.g. Gluteus Maximus) work closer to their optimal length whilst contributing to hip extension.