Search

The relationship between muscle mass and strength is complex as it can be influenced by several neurological factors. Variations in the type of training and its mechanisms involved, such as strength- or hypertrophy-oriented training, may influence this relationship in different ways (Carvalho et al., 2022). In addition, the relationship between muscle stiffness and strength remains unclear (Akagi et al., 2016; Mannarino et al., 2019). Thus, this research aimed to investigate the potential correlation between the strength levels, measured by the 10-repetition maximum (10RM), across different ranges of motion (ROM) in the barbell bench press exercise (BP) to the cross-sectional area (CSA) and shear modulus (= indication for stiffness) of the muscles primarily engaged in the exercise. Twenty-one resistance-trained participants (age 27.1 ± 3.4 years) volunteered in this study. The CSA and muscle shear modulus were assessed in a resting position with ultrasound imaging using an ultrasound system (Supersonic Imaging, Aix-en-Provence, France). CSA ultrasound images were captured with panoramic mode for the pectoralis major and the triceps brachii long head. Muscle shear modulus was measured for the pectoralis major, the anterior deltoid, and the triceps brachii long head using shear wave elastography (SWE). Additionally, participants were assessed for their 10RMs of the three types of BP variations, a full ROM and two partial ROMs, the upper half and lower half of the full movement. Data analyses revealed significant correlations between all BP variations and the medial and lateral CSA of the pectoralis major with correlations ranging from r = 0.775 to r = 0.832 (p = 0.001). Significant correlations were also found for the proximal CSA of the triceps brachii long head with the strength values of all tested BP variations with correlations ranging from ρ = 0.492 to ρ = 0.494 (p = 0.028 to p = 0.027). The distal CSA of the triceps brachii did only correlate significantly with the lower ROM BP (r = 0.484, p = 0.026). No significant correlations were found between the SWE of the measured muscles and the bench press variations tested. Additionally, no differences were observed in the correlations between the BP variations. Correlations between 10RM strength levels and the CSA of the pectoralis, and to a lesser extent, the triceps muscle, show the significance of muscle mass for strength in resistance-trained individuals. This finding aligns with a previous training study that examined the hypertrophic effects of bench press exercises on various muscles (Ogasawara et al., 2012). The study revealed that although both the pectoralis and triceps muscles increased in size, the triceps tended to plateau earlier. This suggests that the pectoralis muscle has a greater capacity for muscle volume growth and, consequently, a higher potential for force production. Finally, SWE measurements revealed no significant correlation with BP variations, implying that muscle stiffness may not play as critical a role in 10RM performance as muscle CSA does. This conclusion aligns with other studies that could not find significant changes in muscle stiffness using SWE following resistance training interventions (Dankel & Razzano, 2020). References Akagi, R., Shikiba, T., Tanaka, J., & Takahashi, H. (2016). A six-week resistance training program does not change shear modulus of the triceps brachii. Journal of Applied Biomechanics, 32(4), 373–378. https://doi.org/10.1123/jab.2015-0290 Carvalho, L., Junior, R. M., Barreira, J., Schoenfeld, B. J., Orazem, J., & Barroso, R. (2022). Muscle hypertrophy and strength gains after resistance training with different volume-matched loads: A systematic review and meta-analysis. Applied Physiology, Nutrition, and Metabolism, 47(4), 357–368. https://doi.org/10.1139/apnm-2021-0515 Dankel, S. J., & Razzano, B. M. (2020). The impact of acute and chronic resistance exercise on muscle stiffness: A systematic review and meta-analysis. Journal of Ultrasound, 23(4), 473–480. https://doi.org/10.1007/s40477-020-00486-3 Mannarino, P., Matta, T. T. D., & Oliveira, L. F. D. (2019). An 8-week resistance training protocol is effective in adapting quadriceps but not patellar tendon shear modulus measured by Shear Wave Elastography. PLoS ONE, 14(4), Article e0205782. https://doi.org/10.1371/journal.pone.0205782 Ogasawara, R., Thiebaud, R. S., Loenneke, J. P., Loftin, M., & Abe, T. (2012). Time course for arm and chest muscle thickness changes following bench press training. Interventional Medicine and Applied Science, 4(4), 217–220. https://doi.org/10.1556/imas.4.2012.4.7

Extended field-of-view ultrasound (US) imaging, also known as panoramic US, represents a technical advance that allows for complete visualization of large musculoskeletal structures, which are often limited in conventional 2D US images. Currently, there is no evidence examining whether the experience of examiners influences muscle shape deformations that may arise during the glide of the transducer in panoramic US acquisition. As no studies using panoramic US have analyzed whether two examiners with differing levels of experience might obtain varying scores in size, shape, or brightness during the US assessment of the rectus femoris muscle, our aim was to analyze the inter-examiner reliability of panoramic US imaging acquisition in determining muscle size, shape, and brightness between two examiners. Additionally, we sought to investigate whether the examiners' experience plays a significant role in muscle deformations during imaging acquisition by assessing score differences. Shape (circularity, aspect ratio, and roundness), size (cross-sectional area and perimeter), and brightness (mean echo intensity) were analyzed in 39 volunteers. Intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC), and coefficient of absolute errors (CAE%) were calculated. All parameters evaluated showed no significant differences between the two examiners (p > 0.05). Panoramic US proved to be reliable, regardless of examiner experience, as no deformations were observed. Further research is needed to corroborate the validity of panoramic US by comparing this method with gold standard techniques. [ABSTRACT FROM AUTHOR]

Extended field-of-view ultrasound (US) imaging, also known as panoramic US, represents a technical advance that allows for complete visualization of large musculoskeletal structures, which are often limited in conventional 2D US images. Currently, there is no evidence examining whether the experience of examiners influences muscle shape deformations that may arise during the glide of the transducer in panoramic US acquisition. As no studies using panoramic US have analyzed whether two examiners with differing levels of experience might obtain varying scores in size, shape, or brightness during the US assessment of the rectus femoris muscle, our aim was to analyze the inter-examiner reliability of panoramic US imaging acquisition in determining muscle size, shape, and brightness between two examiners. Additionally, we sought to investigate whether the examiners’ experience plays a significant role in muscle deformations during imaging acquisition by assessing score differences. Shape (circularity, aspect ratio, and roundness), size (cross-sectional area and perimeter), and brightness (mean echo intensity) were analyzed in 39 volunteers. Intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC), and coefficient of absolute errors (CAE%) were calculated. All parameters evaluated showed no significant differences between the two examiners (p > 0.05). Panoramic US proved to be reliable, regardless of examiner experience, as no deformations were observed. Further research is needed to corroborate the validity of panoramic US by comparing this method with gold standard techniques.

The abdominal muscles are vital in providing core stability for functional movements during most activities. There is a correlation between side asymmetry of these muscles and dysfunction. Thus, the purpose of this study was to evaluate and compare trunk muscle morphology and trunk rotational strength between sprint hurdlers, an asymmetrical sport, and sprinters, a symmetrical sport. Twenty-one trained collegiate sprint hurdlers and sprinters were recruited for the study (Hurdlers: 4M, 7F; Sprinters: 8M, 2F), average age (years) hurdlers: 20 ± 1.2; sprinters: 20.4 ± 1.9, height (cm) hurdlers: 172.6 ± 10.2; sprinters: 181.7 ± 4.5, and weight (kg) hurdlers: 67.6 ± 12.0; sprinters: 73.9 ± 5.6. Using real-time ultrasound, panoramic images of the internal oblique (IO) and external oblique (EO) were obtained at rest and contracted (flexion and rotation) in a seated position for both right and left sides of the trunk. While wearing a specially crafted shoulder harness, participants performed three maximal voluntary trunk rotational contractions (MVC). The three attempts were then averaged to obtain an overall MVC score for trunk rotation strength. Average MVC trunk rotational strength to the right was greater among all participants, p < 0.001. The IO showed greater and significant thickness changes from resting to contracted state than the EO, this was observed in all participants. The IO side asymmetry was significantly different between groups p < 0.01. Hurdlers, involved in a unilaterally demanding sport, exhibited the expected asymmetry in muscle morphology and in trunk rotational strength. Interestingly, sprinters, although involved in a seemingly symmetrical sport, also exhibited asymmetrical trunk morphology and trunk rotational strength. [ABSTRACT FROM AUTHOR]

Panoramic ultrasound (US) is a novel method used to assess linear dimensions, cross-sectional area, fatty infiltrate and echo-intensity features of muscles that cannot be measured with B-mode US. However, a structured overview of its validity and reliability is lacking. MEDLINE, PubMed, SCOPUS and Web of Science databases were systematically searched for studies evaluating reliability or validity data on panoramic US imaging to determine the muscular morphology and/or quality of skeletal muscles. Most studies had acceptable methodological quality. Seventeen studies analyzing reliability (n = 16) or validity (n = 5) were included. Twelve studies assessed cross-sectional area, seven studies assessed echo-intensity, five assessed linear dimensions (fascicle/tendon length, muscle/subcutaneous adipose thickness or between-structure distance) and one assessed intramuscular fat. Panoramic US seems to be a reliable and valid tool for the assessment of muscle morphology and quality in healthy populations at specific locations, particularly the lower extremities. Studies including scanning procedures are needed to confirm these findings in locations not included in this revision and in both clinical and healthy populations. [ABSTRACT FROM AUTHOR]

This study examined whether the association between hamstring (H) and quadriceps (Q) strength with size depends on the region and the muscle used to examined cross-sectional area (CSA). Maximum isometric contraction knee extension and flexion torque was obtained from 20 young participants while Q and H CSA was recorded using extended field of view ultrasonography at four sections along the thigh. Stepwise linear regression models using the maximum CSA of individual muscles showed a significant association of quadriceps (R2 = 0.793) and hamstring (R2 = 0.275) CSA with MVC torque (p < 0.05). The association was lower when maximum or section-specific muscle group CSAs were used as indices of size. The H:Q CSA ratio showed a significant association (R2 = 0.275, p < 0.05) and a moderate correlation (r = 0.48) with H:Q torque ratio. These results indicated that the association between muscle CSA and strength differs between the knee extensors and flexors. Amongst the various indices of muscle size, the combination of maximum CSA values of each muscle displayed the greatest relationship between strength and CSA. The H:Q CSA ratio can explain a significant but small part of the H:Q isometric strength ratio. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to compare biceps femoris long head (BFlh) fascicle length (Lf) obtained with different ultrasound-based approaches: 1) single ultrasound images and linear Lf extrapolation, 2) single ultrasound images and one of two different trigonometric equations (termed equations A and B), and 3) extended field of view (EFOV) ultrasound images. Methods: Thirty-seven elite alpine skiers (21.7 ± 2.8 yr) without a previous history of hamstring strain injury were tested. Single ultrasound images were collected with a 5-cm linear transducer from BFlh at 50% femur length and were compared with whole muscle scans acquired by EFOV ultrasound. Results: The intrasession reliability (intraclass correlation coefficient [ICC3,k]) of Lf measurements was very high for both single ultrasound images (i.e., Lf estimated by linear extrapolation; ICC3,k = 0.96–0.99, SEM = 0.18 cm) and EFOV scans (ICC3,k = 0.91–0.98, SEM = 0.19 cm). Although extrapolation methods showed cases of Lf overestimation and underestimation when compared with EFOV scans, mean Lf measured from EFOV scans (8.07 ± 1.36 cm) was significantly shorter than Lf estimated by trigonometric equations A (9.98 ± 2.12 cm, P < 0.01) and B (8.57 ± 1.59 cm, P = 0.03), but not significantly different from Lf estimated with manual linear extrapolation (8.40 ± 1.68 cm, P = 0.13). Bland–Altman analyses revealed mean differences in Lf obtained from EFOV scans and those estimated from equation A, equation B, and manual linear extrapolation of 1.91 ± 2.1, 0.50 ± 1.0, and 0.33 ± 1.0 cm, respectively. Conclusions: The typical extrapolation methods used for estimating Lf from single ultrasound images are reliable within the same session, but not accurate for estimating BFlh Lf at rest with a 5-cm field of view. We recommend that EFOV scans are implemented to accurately determine intervention-related Lf changes in BFlh. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the reliability and validity of ultrasonography for measurement of hamstring muscle and semitendinosus (ST) tendon cross-sectional area (CSA). On two consecutive days, muscle anatomical CSA (ACSA) and ST tendon CSA were measured at standardized positions (30%-80% of thigh length; half the distance from the distal muscle-tendon junction to the popliteal crease) on 12 legs using ultrasonography and compared with corresponding magnetic resonance imaging measures. Inter-day intraclass correlation coefficients were good-to-excellent (0.882-0.996) for all assessed muscle and tendon sites. The limits of agreement widths were narrowest (range: 17%-52%) when muscle ACSA was large but were wide at sites with relatively small ACSA (≤184%) and for ST tendon CSA (range: 72%). Results suggest ultrasound-based measures of individual hamstring muscle maximal ACSA are reliable and valid and ST tendon CSA measures are reliable but require comparison with cadaveric or intra-operative measurements to verify validity. [ABSTRACT FROM AUTHOR]

Previous studies analyzing morphometry of posterior cervical muscles with ultrasound (US) imaging have mainly used Brightness mode (B-mode). Our aim was to investigate the intra-examiner reliability of panoramic US imaging for assessing posterior-lateral cervical muscle layers. Panoramic US images of the neck at C4/C5 level were acquired in 25 asymptomatic subjects (40% women; mean age: 24 years) by an experienced assessor. The cross-sectional area (CSA) of the upper trapezius, splenius, semispinalis, multifidi, rotators, and levator scapulae was measured from panoramic US scans on two separate days. Intra-class correlation coefficients (ICC3,1), standard error of measurement (SEM), minimal detectable change (MDC) and mean, absolute and percent errors were calculated. In general, intra-examiner reliability was excellent with ICC3,1 ranging from 0.978 (trapezius) to 0.993 (semispinalis). The SEM ranged from 0.02 (multifidus) to 0.07 (semispinalis/levator), whereas the MDC ranged from 0.05 (cervical multifidus) to 0.19 (levator/semispinalis). Absolute error was lower than 0.11 cm2 (levator/semispinalis). No differences between males and females were found. This study found that intra-examiner/rater reliability of panoramic US imaging was excellent for assessing the CSA of the posterior-lateral neck extensor muscles in asymptomatic subjects. The current findings suggest that panoramic US may be a reliable technique for examining the size of the cervical extensor muscles in both males and females.

Background The strong link between reduced muscle mass and morbidity and mortality highlights the urgent need for simple techniques that can monitor change in skeletal muscle cross-sectional area (CSA). Our objective was to examine the validity of panoramic ultrasound to detect change in quadriceps and gastrocnemius size in comparison with magnetic resonance imaging (MRI) in subjects randomized to 70 days of bed rest (BR) with or without exercise. Methods Panoramic ultrasound and MRI images of the quadriceps and gastrocnemius muscles were acquired on the right leg of 27 subjects (26 male, 1 female; age: 34.6 ± 7.8 years; body mass: 77.5 ± 10.0 kg; body mass index: 24.2 ± 2.8 kg/m2; height: 179.1 ± 6.9 cm) before (BR-6), during (BR3, 7, 11, 15, 22, 29, 36, 53, 69), and after (BR+3, +6, +10) BR. Validity of panoramic ultrasound to detect change in muscle CSA was assessed by Bland-Altman plots, Lin's concordance correlation coefficient (CCC), sensitivity, specificity, positive predictive value, and negative predictive value. Results Six hundred ninety-eight panoramic ultrasound CSA and 698 MRI CSA measurements were assessed. Concordance between ultrasound and MRI was excellent in the quadriceps (CCC: 0.78; P < 0.0001), whereas there was poor concordance in the gastrocnemius (CCC: 0.37; P < 0.0006). Compared with MRI, panoramic ultrasound demonstrated high accuracy in detecting quadriceps atrophy and hypertrophy (sensitivity: 73.7%; specificity: 74.2%) and gastrocnemius atrophy (sensitivity: 83.1%) and low accuracy in detecting gastrocnemius hypertrophy (specificity: 33.0%). Conclusions Panoramic ultrasound imaging is a valid tool for monitoring quadriceps muscle atrophy and hypertrophy and for detecting gastrocnemius atrophy. [ABSTRACT FROM AUTHOR]

• No muscle size, shape nor brightness differences were found between US methods. • B-mode and panoramic US demonstrated good-to-excellent concordance. • Panoramic US could be used as an accessible, low-cost and valid imaging tool. Despite panoramic ultrasound imaging (US) is a promising advance for the morphological and histological assessment of large musculature which cannot be entirely assessed using B-mode, there is no evidence assessing if this technology produces muscle deformation during imaging acquisition. We aimed to analyze differences in size, shape and brightness descriptors between B-mode and panoramic US images and to assess the concordance between both methods. Methods We analyzed size (cross-sectional area and perimeter), shape (circularity, aspect ratio and roundness) and brightness (mean echo-intensity) features of cervical multifidus (CM) and short rotators (SR) in 46 healthy volunteers. Images were acquired in B-mode and extended field-of-view mode. For validity analysis, mean differences between methods were calculated. For agreement analysis, intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC) and coefficient of variation (CV%) were calculated. All parameters showed no significant differences between both methods for either CM or SR (P > 0.05). Panoramic US showed excellent concordance with B-mode for assessing all CM parameters (all ICCs > 0.9), while for SR the agreement ranged from good-to-excellent (ICC from 0.861 to 0.978). Panoramic US seems to be a valid tool for assessment of muscle size, shape and brightness as no deformation in comparison with B-mode images was seen. Further research is needed to corroborate these findings comparing panoramic US imaging with Gold Standard methods. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the reliability and validity of using customized templates to acquire panoramic ultrasound (US) images for determining cross-sectional area (CSA) and volume in the vastus lateralis (VL), rectus femoris (RF), medial gastrocnemius (MG) and lateral gastrocnemius (LG). Panoramic US and magnetic resonance imaging (MRI) images were analyzed by two trained investigators. The inter-experimenter reliability (coefficient of variation [CV]) of panoramic US ranged from 2.4% to 4.1% and the intraclass correlation (ICC) ranged from 0.963 to 0.991, whereas the inter-experimenter CV of MRI ranged from 2.8% to 3.8% and the ICC from 0.946 to 0.986. Bland-Altman plots demonstrated high agreement between US and MRI; however, values obtained from MRI were systematically larger than those obtained from US. The present results indicate that using a customized US template provides reliable measures of leg muscle CSA and, thus, could be used to characterize muscle CSA and volume. [Copyright &y& Elsevier]

Ultrasonography advantageously measures skeletal muscle size and quality, but some muscles may be too large to capture with standardized brightness mode (B-mode) imaging. Panoramic ultrasonography can capture more complete images and may more accurately measure muscle size. We investigated measurements made using panoramic compared to B-mode ultrasonography images of the rectus femoris with muscular performance. Concurrently, protein intake plays an important role in preventing sarcopenia; therefore, we also sought to investigate the association between animal-based protein intake (ABPI) and muscular performance. Ninety-one middle-aged adults were recruited. Muscle cross-sectional area (CSA) and thickness were obtained using B-mode and panoramic ultrasound and analyzed with Image J software. Muscular performance was assessed using isokinetic dynamometry, a 30-s chair test, and handgrip strength. Three-day food diaries estimated dietary intakes. Linear regression models determined relationships between measures from ultrasonography and muscular performance. Mixed linear models were used to evaluate the association between ABPI and muscular performance. Muscle CSA from panoramic ultrasonography and ABPI were positively associated with lower-body strength (β ± S.E.; CSA, 42.622 ± 20.024, p = 0.005; ABPI, 65.874 ± 19.855, p = 0.001), lower-body endurance (β ± S.E.; CSA, 595 ± 200.221, p = 0.001; ABPI, 549.944 ± 232.478, p = 0.020), and handgrip strength (β ± S.E.; CSA, 6.966 ± 3.328, p = 0.004; ABPI, 0.349 ± 0.171, p = 0.045). Panoramic ultrasound shows promise as a method for assessing sarcopenia. ABPI is related to better muscular performance. [ABSTRACT FROM AUTHOR]

Previous studies analyzing morphometry of posterior cervical muscles with ultrasound (US) imaging have mainly used Brightness mode (B-mode). Our aim was to investigate the intra-examiner reliability of panoramic US imaging for assessing posterior-lateral cervical muscle layers. Panoramic US images of the neck at C4/C5 level were acquired in 25 asymptomatic subjects (40% women; mean age: 24 years) by an experienced assessor. The cross-sectional area (CSA) of the upper trapezius, splenius, semispinalis, multifidi, rotators, and levator scapulae was measured from panoramic US scans on two separate days. Intra-class correlation coefficients (ICC3,1), standard error of measurement (SEM), minimal detectable change (MDC) and mean, absolute and percent errors were calculated. In general, intra-examiner reliability was excellent with ICC3,1 ranging from 0.978 (trapezius) to 0.993 (semispinalis). The SEM ranged from 0.02 (multifidus) to 0.07 (semispinalis/levator), whereas the MDC ranged from 0.05 (cervical multifidus) to 0.19 (levator/semispinalis). Absolute error was lower than 0.11 cm2 (levator/semispinalis). No differences between males and females were found. This study found that intra-examiner/rater reliability of panoramic US imaging was excellent for assessing the CSA of the posterior-lateral neck extensor muscles in asymptomatic subjects. The current findings suggest that panoramic US may be a reliable technique for examining the size of the cervical extensor muscles in both males and females. [ABSTRACT FROM AUTHOR]

Background: Studies analyzing morphometry of neck extensor musculature have mostly used Magnetic Resonance Imaging (MRI). Panoramic Ultrasound View could be used for obtaining high-quality 2D cross-sectional images with a wide field of view more cost-effectively imaging acquisition by creating an automatic construction of 2D cross-sectional images., Objective: To measure neck extensors cross-sectional area (CSA) using panoramic ultrasound view in healthy subjects., Design: Cross-sectional study., Methods: Panoramic B-mode ultrasound images of the neck extensor muscles at C4/C5 level were acquired in 25 healthy subjects (40% women, mean age: 24 ± 5 years) by an experienced assessor. The CSA of the upper trapezius, splenius (layer), semispinalis (layer), multifidi, short rotators, and levator scapulae were calculated. The relative percentage in the total neck extensor muscle volume of each CSA was also determined. Sex and side-to-side comparisons were conducted., Results: Men showed larger CSAs than women in all muscles (all, P < 0.01). No side-to-side differences were found in either men or women (all, P > 0.05). Significant positive associations between CSA with weight (r: 0.654 to 0.375, P < 0.01), height (r: 0.386 to 0.581, P < 0.05), and BMI (r: 0.369 to 0.563, P < 0.05) were found. Men showed greater percentage of upper trapezius and semispinalis muscle layers than women (P < 0.01), whereas women had a greater percentage of levator scapulae muscle than men (P < 0.01) from the total volume of the neck extensors. No side-to-side differences were found either., Conclusions: The current study describes CSA, as assessed with panoramic ultrasound view, of the neck extensors in healthy people. Men exhibited greater CSA than women with no side-to-side differences., (Copyright © 2020 Elsevier Ltd. All rights reserved.)