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Updated: Jun 7, 2026
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Comparative Analysis of Lower Limb Kinematics between the Initial and Terminal Phase of 5km Treadmill Running
Published on: July 17, 2020
Changes in running kinematics, kinetics, and spring-mass behavior over a 24-h run
Jean-Benoît Morin1, Pierre Samozino, Guillaume Y Millet
1Université de Lyon, Saint Etienne, France. jean.benoit.morin@univ-st-etienne.fr
Medicine and Science in Sports and Exercise
|October 22, 2010
Summary
During a 24-hour treadmill run (24TR), runners adapted their mechanics by increasing step frequency and stiffness. This running adaptation reduced ground reaction forces and leg length changes, potentially protecting the musculoskeletal system.
Area of Science:
- Sports Science
- Biomechanics
- Human Physiology
Background:
- Ultralong-distance running presents unique physiological and biomechanical challenges.
- Understanding adaptive strategies in running mechanics is crucial for injury prevention and performance optimization.
Purpose of the Study:
- To investigate alterations in running mechanics and spring-mass behavior during a 24-hour treadmill run (24TR).
Main Methods:
- Ten experienced ultralong-distance runners underwent kinematic and kinetic assessments.
- Measurements included ground reaction forces (GRF) and spring-mass characteristics using an instrumented treadmill.
- Data were collected at baseline, every 2 hours, and post-24TR at a standardized speed (10 km/h).
Main Results:
- Significant changes in running mechanics were observed throughout the 24TR.
- Average step frequency increased by 4.9% due to shorter contact times.
- Leg and vertical stiffness increased by 9.9% and 8.6% respectively, while maximal GRF and leg length change decreased.
Conclusions:
- Running during a 24TR involves a shift towards higher oscillating frequency and stiffness.
- These adaptations reduce ground reaction forces and eccentric load during the support phase.
- This biomechanical adjustment may mitigate musculoskeletal stress during prolonged running.
