A role for proprioception in the selection of economical gaits

Humans typically prefer metabolically economical gait patterns, as evidenced by increases in metabolic cost that accompany large deviations from the preferred step length and step width. Alterations of the mechanical context tend to evoke changes in the preferred gait mechanics that are consistent with adaptation toward gait economy. However, the mechanism underlying the selection of economical gait patterns is not presently clear. The link between gait mechanics and metabolic cost suggests that proprioceptive feedback providing information about the body's mechanical state could play a role in selecting metabolically economical gait patterns. To investigate this possibility, we have used non-invasive peripheral vibration to grossly manipulate proprioceptive feedback in several walking contexts, while monitoring the effects on gait mechanics and economy. Our results suggest that proprioceptive feedback can contribute to gait economy in combination with multiple other sensory feedback sources, with the most relevant feedback source determined by the specific task demands.