 The relationship between mechanical work and step frequency can be described by formula_9 for the step-to-step transitions, where formula_7 is the mechanical work rate and formula_11 is the step frequency.Rate of metabolic cost also follows this relationship.The impact of cadence on leg swing metabolic cost is approximated as formula_12, where formula_13 is the rate of metabolic cost and formula_11 is the step frequency

Similar to selection of stride length and frequency, humans also select for a metabolically optimal step width.