Fig 4. Accuracy of the Three Methods.

Shown are means and standard deviations of the predicted energetic minima. We use the subjects’ preferred step frequency as ‘ground truth’ for comparison [15]. All three methods, on average, identify energetic minima near the subjects preferred cadence. The variance in the outcomes of the proposed Instantaneous Cost methods is only slightly higher than that of the established Steady-State Cost Mapping. There is no significant difference between the absolute error of the three methods.