| Changes in Running Kinematics, Kinetics, and Spring-Mass Behavior over a 24-h Run. | |
| | |
MedLine Citation:
|
PMID: 20962690 Owner: NLM Status: In-Data-Review |
Abstract/OtherAbstract:
|
PURPOSE: : This study investigated the changes in running mechanics and spring-mass behavior over a 24-h treadmill run (24TR). METHODS: : Kinematics, kinetics, and spring-mass characteristics of the running step were assessed in 10 experienced ultralong-distance runners before, every 2 h, and after a 24TR using an instrumented treadmill dynamometer. These measurements were performed at 10 km·h, and mechanical parameters were sampled at 1000 Hz for 10 consecutive steps. Contact and aerial times were determined from ground reaction force (GRF) signals and used to compute step frequency. Maximal GRF, loading rate, downward displacement of the center of mass, and leg length change during the support phase were determined and used to compute both vertical and leg stiffness. RESULTS: : Subjects' running pattern and spring-mass behavior significantly changed over the 24TR with a 4.9% higher step frequency on average (because of a significantly 4.5% shorter contact time), a lower maximal GRF (by 4.4% on average), a 13.0% lower leg length change during contact, and an increase in both leg and vertical stiffness (+9.9% and +8.6% on average, respectively). Most of these changes were significant from the early phase of the 24TR (fourth to sixth hour of running) and could be speculated as contributing to an overall limitation of the potentially harmful consequences of such a long-duration run on subjects' musculoskeletal system. CONCLUSIONS: : During a 24TR, the changes in running mechanics and spring-mass behavior show a clear shift toward a higher oscillating frequency and stiffness, along with lower GRF and leg length change (hence a reduced overall eccentric load) during the support phase of running. |
| | |
Authors:
|
Jean-Benoît Morin; Pierre Samozino; Guillaume Y Millet |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: Medicine and science in sports and exercise Volume: 43 ISSN: 1530-0315 ISO Abbreviation: Med Sci Sports Exerc Publication Date: 2011 May |
Date Detail:
|
Created Date: 2011-04-26 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 8005433 Medline TA: Med Sci Sports Exerc Country: United States |
Other Details:
|
Languages: eng Pagination: 829-36 Citation Subset: IM; S |
Affiliation:
|
Université de Lyon, Saint Etienne, FRANCE; and Laboratoire de Physiologie de l'Exercice - LPE EA4338, Saint-Etienne, FRANCE. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Effects of body mass index and tilt angle on output of two wearable activity monitors.
Next Document: Physiology, power output, and racing strategy of a race across america finisher.