Postgraduate Profiles

Kirsty McDonald

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Thesis: At What Cost? Discovering Energetic and Stability Optimality Criteria in Human Locomotion

Classic locomotion experiments have led to an understanding of walking with optimization of energy cost often being cited as the determining principle underpinning human gait selection. However, the objectives of locomotion are not limited to minimizing metabolic demands; humans must also avoid injury, undergo bouts of maximum ‘high risk’ performance and maintain mechanical stability. To date, the relationship between energetic and stability optimization has not been thoroughly explored in walking.

The overarching aim of this project is therefore to explore and refine energetic, cost-based hypotheses of neuromuscular function in walking gait to encompass the adapted, goal-directed, locomotor behaviour of adults in both stable and unstable environments. This will be achieved by (1) externally enhancing and reducing mechanical gait stability to determine whether preferred walking speed (PWS) conforms to energetic and/or stability optimization criteria during normal, perturbed and stabilized gait; (2) modelling the mechanics of the leg muscles and their energy cost of stabilization under various degrees of stability; (3) uncoupling the energetic and stability optimality criteria to determine whether minimizing energy cost or instability is prioritized when the two are pitted against each other.

Why my research is important

Discovering the optimality criteria that dictate biomechanical function in human gait is crucial to understanding the very essence of how we locomote, which could have further implications for clinicians treating populations characterized by gait instability (e.g. elderly) and to the design of our built environment, among others.

Mar 2014

Mar 2017