As the speed of human terrestrial locomotion increases during walking or decreases during running, a speed must be reached at which a gait transition naturally occurs. The overall purpose of this project was to identify factors that are important in the determination of the gait transition speed. A widespread assumption of previous researchers is that the gait transition takes place at speeds which minimize metabolic energy consumption. The purpose of the first experiment of this investigation was to determine, by direct measurements, whether this was a valid assumption. If this assumption was not valid, then the effect other variables (anthropometric, kinematic, and kinetic) on the preferred gait transition speed (PTS) would be examined in three subsequent experiments.

Although the energetically optimal transition speed (EOTS) found during this study (2.24 m-s⁻¹) was less than reported by previous researchers (2.36 m-s⁻¹), the EOTS was significantly greater than the PTS of 2.06 m-s⁻¹ found for the 20 subjects participating in the first experiment, suggesting that the gait transition during human locomotion does not take place in order to minimize metabolic energy consumption. Leg length was the only anthropometric variable found to correlate significantly with the PTS, although the correlation was low (r=0.38). No kinetic variables were found to be determinants of the PTS. The only kinematic variable found to be a determinant of the PTS was the maximum ankle angular velocity. It was concluded that the gait transition during human locomotion occurs when the ankle dorsiflexion velocity reaches a critical level signaled by force and velocity feedback from the ankle dorsiflexor muscles, primarily the tibialis anterior.