Effects of Acute Supine rest and Hydration Status on Mid-Thigh Muscle Size and Quality as Measured by Ultrasonography Public Deposited

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  • March 21, 2019
  • Shea, Nicholas
    • Affiliation: College of Arts and Sciences, Department of Exercise and Sport Science
  • Ultrasonography (US) has emerged as a method of assessing muscle size and quality.  These measurements may be confounded by fluid shifts resulting from a change in position. The purpose of this study was to investigate the time course of fluid shifts and its influence on muscle size and quality measurements. Thirty-five males were recruited for the study.  Ultrasound images and segmental bioelectrical spectroscopy assessments of the right thigh occurred after transition to supine and sequentially every five minutes, to 30 minutes. Subcutaneous fat and corrected echo intensity (EI) for the young and older men showed a significant age × time interaction (P<0.05).  Changes in muscle size were noted after 20 minutes, whereas changes in corrected EI were seen after 10 minutes only in the older men. Our findings suggest that muscle size and quality US measurements should be taken within the first 10 minutes of supine rest.
Date of publication
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Rights statement
  • In Copyright
  • Smith-Ryan, Abbie
  • Ryan, Eric
  • Pexa, Brett
  • Master of Arts
Degree granting institution
  • University of North Carolina at Chapel Hill Graduate School
Graduation year
  • 2017

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