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Measuring muscle quality: associations between echo intensity and normalized strength and power
Hayden K Giuliani1,2, Megan R Laffan1, Abigail J Trivisonno1
1Neuromuscular Assessment Laboratory, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America.
Physiological Measurement
|February 26, 2021
Summary
Muscle echo intensity, a measure of muscle quality, correlates with limb fat mass but not lean mass. This suggests distinct definitions are needed for imaging-derived versus strength-based muscle quality assessments.
Area of Science:
- Exercise Physiology
- Biomedical Engineering
- Kinesiology
Background:
- Muscle quality is crucial for health and performance.
- Current measures of muscle quality lack a standardized definition.
- Common assessments include ultrasound imaging and normalized strength.
Purpose of the Study:
- To investigate the association between vastus lateralis echo intensity (EI) and normalized peak torque (PT) and power (PP).
- To determine if these measures correlate with thigh lean mass (TLM) or thigh fat mass (TFM).
Main Methods:
- 39 participants' body composition was assessed using dual-energy x-ray absorptiometry.
- Muscle EI was measured via ultrasonography.
- Maximal PT and PP were assessed using a dynamometer and normalized to TLM and TFM.
Main Results:
- Higher muscle EI was significantly associated with lower PT/TFM and PP/TFM (r = -0.74 to -0.70, P < 0.001).
- No significant association was found between muscle EI and PT/TLM or PP/TLM (P ≥ 0.205).
Conclusions:
- Muscle EI and normalized strength/power may not be interchangeable measures of muscle quality.
- Muscle EI appears more sensitive to limb adiposity than to lean mass.
- Consistent, distinct definitions are recommended for future research on muscle quality.
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