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Updated: Jun 4, 2026
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Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds
Published on: August 25, 2020
Braking and propulsive impulses increase with speed during accelerated and decelerated walking
Carrie L Peterson1, Steven A Kautz, Richard R Neptune
1Department of Mechanical Engineering, The University of Texas at Austin, TX 78712, USA.
Gait & Posture
|March 2, 2011
Summary
Changing walking speed relies on braking and propulsive ground reaction force impulses. Braking impulses are modulated more than propulsive impulses to adjust speed, impacting joint moments and potentially minimizing metabolic cost.
Area of Science:
- Biomechanics
- Human locomotion
- Gait analysis
Background:
- Daily activities require acceleration and deceleration, which are more demanding than steady-state walking.
- Walking speed is controlled by anterior-posterior (AP) ground reaction force (GRF) impulses.
Purpose of the Study:
- To investigate AP impulses during accelerated and decelerated walking across various speeds.
- To understand how speed changes affect gait parameters and joint moments.
Main Methods:
- Collected kinematic and GRF data from 10 healthy subjects on an instrumented treadmill.
- Subjects performed steady-state walking and trials at four rates of acceleration/deceleration (0-1.8 m/s).
- Used mixed regression models to analyze relationships between speed, AP impulses, step parameters, and joint moment impulses.
Main Results:
- Braking and propulsive impulses increased with walking speed.
- Braking impulse showed a stronger relationship with speed than propulsive impulse, indicating greater modulation for speed changes.
- Joint moment impulses (hip, knee, ankle) were related to braking and propulsive impulses.
- Step length and frequency increased with speed, potentially to minimize metabolic cost.
Conclusions:
- Braking impulse is a key variable modulated for speed control during non-steady-state walking.
- Gait parameters (step length, frequency) may be adjusted to optimize metabolic efficiency during acceleration and deceleration.
- Findings provide a basis for studying motor control in individuals with gait pathologies during dynamic walking tasks.
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