Intermittent Cold Exposure Causes a Muscle-Specific Shift in the Fiber Type Composition in Rats

Abstract

We examined the effect of long-term intermittent cold exposure on the fiber type composition of the predominantly type I soleus and the predominantly type IIb extensor digitorum longus (EDL) muscles of rats. Cold exposure was accomplished by submerging the rats in shoulder-deep water, maintained at 20+0.5 degrees C, for 1 h/day, 5 days/wk, for <19 wk. The efficacy of the treatment was tested by subjecting both groups to 20 degrees C water for 45 min while rectal temperature (Tre) and 02 consumption (Vo2) were measured. The cold-exposed group displayed a 22% smaller reduction in Tre (P<0.05) at the end of the exposure and 23% greater Vo2 (P<0.05) during the same period. The present study demonstrates that intermittent cold exposure induces a type I-to-type IIa transformation in the soleus muscle while having no influence on the EDL muscle.... Acclimation, Hypothermia, Mitochondria, Metabolism

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1993
Accession Number
ADA269765

Entities

People

  • S. H. Constable
  • T. J. Walters

Organizations

  • Armstrong Laboratory

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Acclimatization
  • Adipose Tissue
  • Air Force
  • Air Force Facilities
  • Animals
  • Classification
  • Cold Water
  • Connective Tissue
  • Data Acquisition
  • Deep Water
  • Digestive System Processes
  • Laboratory Animals
  • Muscles
  • Skeletal Muscle
  • Thyroid Hormones
  • Water

Readers

  • Exercise and Sports Science.