Introduction: The aim of this study was to examine the associations between quadriceps muscle functionality features in nonactive older men to determine predictors of functional performance.
Methods: Quadriceps functional parameters, including quadriceps echo intensity (QEI), rate of torque development (RTD), and the 30 s sit-to-stand test (30SS), were assessed in 50 healthy sedentary older men (66 ± 5.4 years). RTD/QEI ratios were also calculated to identify the best predictor of functional performance.
Results: 30SS performance was associated with RTD, muscle thickness, RTD-50/QEI, RTD-100/QEI, RTD-50/QEI/WBM, and RTD-100/QEI/WBM. A multiple stepwise linear regression demonstrated that QEI was the best single predictor of functional performance, explaining ∼30% of the 30SS variance.
Conclusions: These results indicate that QEI was the strongest contributor to functionality of nonactive older men, suggesting that QEI may be an alternative tool for screening of muscle impairment that leads to decreased functional performance in this population. Muscle Nerve 55: 9-15, 2017.
Keywords: aging; functionality; muscle quality; muscular performance; ultrasonography.
© 2016 Wiley Periodicals, Inc.