Dataset of energetics and biomechanics of self-paced and fixed speed treadmill walking at multiple speeds

Data collection process: This dataset includes continuously measured walking biomechanics collected using three-dimensional motion capture and gas exchanges of 18 healthy participants (9 male/9 female, mean ± standard deviation age 24.8 ± 3.3 years, height 1.71 ± 0.81 meter, weight 65.9 ± 8.1 kilogram). Walking biomechanics were recorded during four different self-paced speeds (comfortable, very slow, slow, fast) in randomized order and four fixed-paced speeds on an instrumented treadmill. The average walking speed during the last two minutes of a 6 minute self-paced walking familiarization period was determined as the comfortable walking speed and used to set the target speed ranges for the other self-paced conditions: slow (20% slower than comfortable), very slow (40% slower) and fast (20% faster) Oxygen consumption (O₂) and carbon dioxide (CO₂) production were measured continuously and computed at 5-second intervals throughout the resting metabolic rate (RMR) measurement and walking trials. RMR (J·24 hours) was computed from the average O₂ and CO₂ measured during the last 5 minutes of the 35 minutes RMR measurement using Weir's non-protein equation. The energy consumption of walking (J·min^-1) at each speed was computed from the average O₂ and CO₂ measured during the last 2 minutes of each condition using similar procedures. RMR (J·min^-1) was subtracted from the energy consumption of walking to determine net walking energy consumption. The net cost of walking was then expressed as J·kg·0.67^-1·m^-1. All participants avoided strenuous activity 24 hours, and eating and drinking (with the exception of water) up to 3hours before the session. Height was measured using a stadiometer (SECA, model 213, Hamburg, Germany). Body mass was measured by force platforms.

Analysis performed: Both the exported data files from the CAREN software (D-flow) (.mox files), and processed data files with a custom-made Matlab script are included. Marker and force plate data in the .mox and processed files were low-pass filtered using a 2^nd order Butterworth with a cut-off frequency of 6 Hz. C3D files with raw marker and ground reaction force data are available upon request.

Data: Continuously measured spatiotemporal parameters, energetics, 3D lower lumb plus trunk kinematics, 3D kinetics and surface muscle activation during walking at both self-paced and imposed(fixed) speeds on a treadmill. Resting metabolism.

Reuse potential: 1) Assessing self-paced and fixed speed treadmill walking biomechanical and energetics, 2) assessing biomechanics and energy expenditure at multiple or particular speeds, 3) investigating the relationship between walking biomechanics and energetics, 4) reference database of walking biomechanics and energetics of healthy adults.