Energy expenditure does not solely explain step length-width choices during walking

Area of Science:

• Biomechanics
• Human locomotion
• Gait analysis

Background:

• Preferred walking patterns in young adults often align with energetic optima.
• However, individuals can adopt diverse step lengths and widths, influencing both energy use and preference.

Purpose of the Study:

• To investigate the relationship between preferred step length-width patterns and energy expenditure.
• To test the hypothesis that metabolic energy expenditure alone does not fully explain preferred stepping patterns.

Main Methods:

• A two-alternative forced-choice paradigm was used with 15 participants walking on an oversized treadmill.
• Participants chose between two prescribed stepping patterns, with choices adapted to identify equally preferred patterns.
• Energy expenditure was measured for these equally preferred patterns.

Main Results:

• Equally preferred step length-width patterns exhibited significant differences in energy expenditure (P<0.001).
• Longer steps, despite higher energy costs, were preferred over shorter, wider steps with lower energy expenditure (P<0.001).
• Only 7 out of 15 participants ranked preferences and perceived energy expenditure identically.

Conclusions:

• Metabolic energy expenditure is not the sole determinant of conscious gait choices.
• Factors beyond energy efficiency influence how individuals select their preferred walking patterns, such as step length and width.