Associations of passive muscle stiffness and muscle echo-intensity with muscle strength
Merve Karapınar1
, Veysel Atilla Ayyıldız2
1Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, Süleyman Demirel University, Isparta, Türkiye
2Department of Radiology, Faculty of Medicine, Süleyman Demirel University, Isparta, Türkiye
Abstract
Objective: Muscle tissue parameters including composition and stiffness of muscle can have an important effect on muscle strength. In this study, we aimed to investigate the relationships between muscle echo-intensity (EI), tendon stiffness and muscle strength in young men and women.
Methods: Ultrasound B-mode images of the Rectus Femoris (RF), Vastus Medialis (VM) and Patellar Tendon (PT) were acquired in fifty-two healthy subjects (mean age; 27.43±5.3 years). RF, VM and PT stiffness were characterized by shear-wave elastography measurements. Quantitative evaluations were performed, including measurement of muscle and tendon thickness and muscle EI. Isometric knee extension muscle strength was measured using hand-held dynamometer.
Results: RF stiffness had a good correlation with muscle strength (r=-0.46, p<0.05) and had a fair correlation with EIRF(r=-0.37,p<0.05), VM stiffness had a good correlation with muscle strength (r=0.42, p<0.05) and had a fair correlation with EIVM (r=-0.43,p<0.05) in women. RF stiffness had a good correlation with muscle strength (r=-0.54, p<0.05), had a good correlation with EIRF(r=-0.41,p<0.05) in men.VM stiffness had a good correlation with muscle strength(r=-0.50; p<0.05), and had a good correlation with EIVM(r=-0.60,p<0.05) in men. EIRF and EIVM had a good relation with muscle strength in men and women (For EIRF; r=-0.46; r=-0.54; for EIVM; r=-0.42; r=-0.50 p<0.05, respectively)
Conclusions: This study demonstrates that there is a relationship between isometric muscle strength and passive muscle stiffness, muscle EI. Additionally, muscle EI affects muscle stiffness in healthy men and women. Our results should be considered in elite athletes for whom the strengthening program is important.
Cite this article as: Karapinar M, Ayyildiz VA. Associations of passive muscle stiffness and muscle echo-intensity with muscle strength. Turk J Sports Med. 2024;59(3):99-104; https://doi.org/10.47447/tjsm.0806
This study was approved by the Suleyman Demirel University University Faculty of Medicine Scientific Research Ethics Committee (Decision number: 258, Date: 28.09. 2022).
Concept – MK, VAA; Design - MK; Supervision – VAA; Materials – Data Collection and/or Processing – MK, VAA; Analysis and Interpretation – MK; Literature Review – MK, VAA; Writing manuscript; MK, VAA; Critical Reviews – MK, VAA. All authors contributed to the final version of the manuscript and discussed the results and contributed to the final manuscript
The authors declared no conflicts of interest with respect to authorship and/or publication of the article.
The authors received no financial support for the research and/or publication of this article.
