Why change gaits? Dynamics of the walk-run transition

J Exp Psychol Hum Percept Perform. 1995 Feb;21(1):183-202. doi: 10.1037//0096-1523.21.1.183.


Why do humans switch from walking to running at a particular speed? It is proposed that gait transitions behave like nonequilibrium phase transitions between attractors. Experiment 1 examined walking and running on a treadmill while speed was varied. The transition occurred at the equal-energy separatrix between gaits, with predicted shifts in stride length and frequency, a qualitative reorganization in the relative phasing of segments within a leg, a sudden jump in relative phase, enhanced fluctuations in relative phase, and hysteresis. Experiment 2 dissociated speed, frequency, and stride length to show that the transition occurred at a constant speed near the energy separatrix. Results are consistent with a dynamic theory of locomotion in which preferred gaits are characterized by stable phase relationships and minimum energy expenditure, and gait transitions by a loss of stability and the reduction of energetic costs.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acceleration
  • Adolescent
  • Adult
  • Energy Metabolism
  • Female
  • Gait*
  • Humans
  • Male
  • Postural Balance
  • Running*
  • Walking*