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Updated: Jun 20, 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
Running from Paris to Beijing: biomechanical and physiological consequences
Guillaume Y Millet1, Jean-Benoît Morin, Francis Degache
1Exercise Physiology Laboratory, Jean Monnet University, Saint-Etienne, France. guillaume.millet@univ-st-etienne.fr
European Journal of Applied Physiology
|September 17, 2009
Summary
Ultra-runners adapt their running pattern to reduce strain, but experience decreased strength and increased energy cost. These changes persist long-term, impacting performance and recovery after extreme endurance running.
Area of Science:
- Exercise Physiology
- Biomechanics
- Sports Science
Background:
- Ultra-endurance running presents unique physiological and biomechanical challenges.
- Understanding adaptations to extreme distances is crucial for athlete health and performance.
Observation:
- An experienced ultra-runner completed 8,500 km in 161 days, averaging 52.8 km daily.
- Physiological and biomechanical parameters were assessed before, immediately after, and 5 months post-run.
Findings:
- Post-run, a 'smoother' running pattern emerged with higher stride frequency and duty factor, reduced aerial time, lower impact forces, and decreased limb energy fluctuations.
- These adaptations correlated with a 6.2% increase in energy cost of running (Cr) and significant loss of knee flexor and extensor strength.
- Five months later, running patterns normalized at low speeds, but strength deficits persisted at high force outputs.
Implications:
- Running pattern modifications may be a compensatory strategy to mitigate the physiological stress of ultra-endurance running.
- Reduced maximal strength appears to be a significant factor influencing these adaptive running strategies.
- Long-term deficits in strength and altered running economy highlight the profound physiological impact of extreme endurance events.
