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Myocellular basis for tapering in competitive distance runners
Nicholas Luden1, Erik Hayes, Andrew Galpin
1Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA.
Journal of Applied Physiology (Bethesda, Md. : 1985)
|March 20, 2010
Summary
A 3-week taper improved race performance in competitive distance runners by enhancing muscle fiber function and altering gene expression, without negatively impacting aerobic fitness.
Area of Science:
- Exercise Physiology
- Molecular Biology
- Sports Science
Background:
- Optimizing performance in competitive distance runners often involves strategic training modifications.
- Tapering, a period of reduced training load, is commonly employed before major competitions.
Purpose of the Study:
- To investigate the physiological adaptations in collegiate distance runners following a 3-week taper.
- To determine the effects of tapering on muscle fiber characteristics, gene expression, and cardiovascular function.
Main Methods:
- Seven collegiate distance runners underwent physiological assessments before and after a 3-week taper.
- Measurements included 8-km race performance, single muscle fiber analysis (Myosin Heavy Chain IIa and I), gene expression post-exercise, and cardiovascular testing.
Main Results:
- Race performance improved by 3% post-taper.
- Significant increases were observed in Myosin Heavy Chain IIa fiber diameter, peak force, and absolute power.
- Tapering altered the post-exercise gene expression profile, attenuating MuRF-1 induction while enhancing MRF4, HSP 72, and MT-2A responses.
Conclusions:
- Tapering promotes beneficial muscle fiber remodeling and alters the transcriptional response to exercise in distance runners.
- These myocellular adaptations provide a physiological basis for improved performance after tapering.
- Tapering effectively enhances performance without compromising aerobic capacity.
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