Echo Intensity Reliability for the Analysis of Different Muscle Areas in Athletes

Abstract

Lanferdini, FJ, Manganelli, BF, Lopez, P, Klein, KD, Cadore, EL, and Vaz, MA. Echo intensity reliability for the analysis of different muscle areas in athletes. J Strength Cond Res 33(12): 3353–3360, 2019—Skeletal muscles' echo intensity (EI) is used as a parameter to evaluate muscle damage and muscle quality after exercise or training. However, recent muscle EI studies have used regions of interest (ROIs) of different sizes for assessing muscle damage and muscle quality, which may lead to different results if the different ROIs from the same muscle are not reliable. Although a maximum rectangular ROI (RET-ROI), included in the muscles' anatomical cross-sectional area, can be used to represent the maximum muscle ROI (MAX-ROI), no studies were found that investigated the reliability of the evaluations of different ROIs for the EI of superficial vs. deep muscles of the thigh. In addition, no studies have evaluated different ROIs in cyclists, at different days and analyzed by different raters. The aim of this study was to evaluate the EI reliability of rectus femoris (RF) and vastus intermedius (VI) muscles of cyclists. Twenty cyclists visited the laboratory 4 times for the evaluation of RF and VI muscles transversal ultrasound images. Echo intensity was determined from grayscale mean values by 2 examiners who performed the analysis with 3 different ROIs: MAX-ROI, RET-ROI, and 1-cm2 ROI (1CM-ROI). The between-ROI EI data reliability showed a strong correlation in both RF (r ≥ 0.79) and VI (r ≥ 0.87) muscles. Bland-Altman tests demonstrated high agreement among RF ROI muscle areas (p > 0.05), with no agreement between the VI areas (p < 0.05). Only the RF muscle MAX-ROI, RET-ROI, and 1CM-ROI areas are similar for EI analysis, with no similarities for the same VI muscle areas.

Reliability of portable electrical impedance myograph SKULPT® for morphological measures of vastus lateralis/ Confiabilidade da impedância elétrica do miógrafo portátil SKULPT® a partir de medidas morfológicas do vastus lateralis

“…Results of reliability of EI (r=0.75) and MT (r=0.99) demonstrated good-excellent values, which agrees with previous studies that evaluated the reliability of the measurements obtained by the US (LANFERDINI et al 2019;LIN et al 2015;PALMER et al 2015;RUAS et al 2017 1). Therefore, we propose that the MQ data could be corrected using Equation 1proposed by the present study, although the Bland-Altman test does not show any differences between EI and MQ measurements.…”

“…US is commonly used for muscle thickness (MT) measurement (BJORNSEN et al 2016;DE BOER et al 2008;LI et al 2013;REEVES et al 2009). However, the US has also been used to quantify echo intensity (EI), which reflects muscle quality (LANFERDINI et al 2019;PALMER et al 2015;RUAS et al 2017; SANTOS; ARMADA-DA-SILVA, 2017). The infiltration of fat and fibrous tissues increases the Brazilian Journal of Development, Curitiba, v.7, n.4, p. 33910-33923apr 2021 number of echoes or reflections from the ultrasound within the muscle, which is directly correlated with increases in EI and, consequently, worsening muscle quality (WATANABE et al 2018).…”

Influence of muscle depth and thickness on ultrasound echo intensity of the vastus lateralis

“…The present study also examined larger ROIs within the image of the VL than Caresio et al. (25) did in the tibialis anterior, and EI reliability improves when larger regions are examined (25,41). Notably, the values for EI DEEP were less than EI FULL , and both were less than EI SUPF in our study, whereas Caresio et al.…”

“…Different muscle fiber arrangements between the VL (unipennate muscle) and the tibialis anterior (circumpennate muscle) may explain these opposing results, as EI heterogeneity within an individual image may be influenced by muscle architecture, independent of muscle depth (25,27). The present study also examined larger ROIs within the image of the VL than Caresio et al (25) did in the tibialis anterior, and EI reliability improves when larger regions are examined (25,41). Notably, the values for EI DEEP were less than EI FULL , and both were less than EI SUPF in our study, whereas Caresio et al reported lower EI of both the superficial and deep portions than EI of the full muscle, indicating that regions of the muscle with higher EI were not included in either the superficial or deep regions selected by Caresio et al (25).…”

Implementing Ultrasound Imaging for the Assessment of Muscle and Tendon Properties in Elite Sports: Practical Aspects, Methodological Considerations and Future Directions

“…Low echo intensity values are considered to be associated with greater muscle quality; in contrast, high echo intensity values are thought to be related to muscle impairment [33]. US has been shown to be a reliable tool for the assessment of muscle quality as echo intensity in different populations [33], including young athletes [36]. Echo intensity has been mainly used to study muscle quality changes in aging [34], although attempts to apply it in a sports setting have been conducted [37][38][39].…”