{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:31:47Z","timestamp":1790037107429,"version":"4.0.1"},"reference-count":25,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,8,25]],"date-time":"2021-08-25T00:00:00Z","timestamp":1629849600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Culture, Sports, Science, and Technology","award":["#18H03200, #20K21774"],"award-info":[{"award-number":["#18H03200, #20K21774"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Skeletal muscle fibrosis occurs with aging and has been suggested to impair muscle performance, thereby decreasing quality of life. Recently, muscle stiffness, a surrogate measure of muscle fibrosis, was noninvasively quantified as the shear modulus using ultrasound shear wave elastography (SWE) in humans. We aimed to investigate thigh muscle stiffness in females and males, respectively, across a broad range of ages by using SWE. Eighty-six community-dwelling Japanese people who were aged 30 to 79 years and did not regularly exercise participated in this study. The vastus lateralis (VL) shear modulus was measured at three different knee joint angles: full extension, 90\u00b0 of flexion, and full flexion. There were no significant main effects of sex or age on the VL shear modulus in full extension or 90\u00b0 of flexion of the knee. However, the VL shear modulus in knee full flexion was significantly smaller in females than in males and increased with age from 47.9 years. The results suggest that the accelerated increase in VL stiffness that occurs after an individual passes their late 40s may be an important therapeutic target for developing effective treatments and programs that preserve and improve quality of life.<\/jats:p>","DOI":"10.3390\/ijerph18178947","type":"journal-article","created":{"date-parts":[[2021,8,26]],"date-time":"2021-08-26T00:19:26Z","timestamp":1629937166000},"page":"8947","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Characteristics of the Passive Muscle Stiffness of the Vastus Lateralis: A Feasibility Study to Assess Muscle Fibrosis"],"prefix":"10.3390","volume":"18","author":[{"given":"Akifumi","family":"Maeda","sequence":"first","affiliation":[{"name":"Faculty of Sport and Health Science, Ritsumeikan University, Shiga 525-8577, Japan"},{"name":"Suntory Global Innovation Center Ltd., Research Institute, Kyoto 619-0284, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maito","family":"Yamagishi","sequence":"additional","affiliation":[{"name":"Faculty of Sport and Health Science, Ritsumeikan University, Shiga 525-8577, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2482-2802","authenticated-orcid":false,"given":"Yuta","family":"Otsuka","sequence":"additional","affiliation":[{"name":"Institute for Health Care Science, Suntory Wellness Ltd., Kyoto 619-0284, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takayuki","family":"Izumo","sequence":"additional","affiliation":[{"name":"Institute for Health Care Science, Suntory Wellness Ltd., Kyoto 619-0284, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomohiro","family":"Rogi","sequence":"additional","affiliation":[{"name":"Institute for Health Care Science, Suntory Wellness Ltd., Kyoto 619-0284, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroshi","family":"Shibata","sequence":"additional","affiliation":[{"name":"Institute for Health Care Science, Suntory Wellness Ltd., Kyoto 619-0284, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masahiro","family":"Fukuda","sequence":"additional","affiliation":[{"name":"Fukuda Clinic, Osaka 532-0003, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takuma","family":"Arimitsu","sequence":"additional","affiliation":[{"name":"Faculty of Sport and Health Science, Ritsumeikan University, Shiga 525-8577, Japan"},{"name":"Undergraduate Department of Human Health, Faculty of Health Care, Hachinohe Gakuin University, Aomori 031-8588, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4284-6317","authenticated-orcid":false,"given":"Yosuke","family":"Yamada","sequence":"additional","affiliation":[{"name":"National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo 162-8636, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naokazu","family":"Miyamoto","sequence":"additional","affiliation":[{"name":"Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3951-5290","authenticated-orcid":false,"given":"Takeshi","family":"Hashimoto","sequence":"additional","affiliation":[{"name":"Faculty of Sport and Health Science, Ritsumeikan University, Shiga 525-8577, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1152\/japplphysiol.00256.2014","article-title":"Intrinsic Stiffness of Extracellular Matrix Increases with Age in Skeletal Muscles of Mice","volume":"117","author":"Wood","year":"2014","journal-title":"J. Appl. Physiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"575","DOI":"10.1007\/s00441-018-2955-2","article-title":"Skeletal Muscle Fibrosis: An Overview","volume":"375","author":"Mahdy","year":"2019","journal-title":"Cell Tissue Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1111\/acel.12578","article-title":"Aging of the Skeletal Muscle Extracellular Matrix Drives a Stem Cell Fibrogenic Conversion","volume":"16","author":"Beezhold","year":"2017","journal-title":"Aging Cell"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1002\/mus.22094","article-title":"Structure and Function of the Skeletal Muscle Extracellular Matrix","volume":"44","author":"Gillies","year":"2011","journal-title":"Muscle Nerve"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/0021-9290(89)90181-4","article-title":"Strain-Induced Reorientation of an Intramuscular Connective Tissue Network: Implications for Passive Muscle Elasticity","volume":"22","author":"Purslow","year":"1989","journal-title":"J. Biomech."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"771","DOI":"10.1016\/j.jbiomech.2010.10.044","article-title":"Elucidation of Extracellular Matrix Mechanics from Muscle Fibers and Fiber Bundles","volume":"44","author":"Meyer","year":"2011","journal-title":"J. Biomech."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"464","DOI":"10.1002\/mus.10446","article-title":"Inferior Mechanical Properties of Spastic Muscle Bundles Due to Hypertrophic but Compromised Extracellular Matrix Material","volume":"28","author":"Lieber","year":"2003","journal-title":"Muscle Nerve"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/S0268-0033(00)00061-9","article-title":"Passive Extensibility of Skeletal Muscle: Review of the Literature with Clinical Implications","volume":"16","author":"Gajdosik","year":"2001","journal-title":"Clin. Biomech."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"284","DOI":"10.1038\/s41598-020-78747-8","article-title":"Non-Invasive Assessment of Skeletal Muscle Fibrosis in Mice Using Nuclear Magnetic Resonance Imaging and Ultrasound Shear Wave Elastography","volume":"11","author":"Bachasson","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2906","DOI":"10.1016\/j.ultrasmedbio.2015.07.011","article-title":"Age-Related Differences in Muscle Shear Moduli in the Lower Extremity","volume":"41","author":"Akagi","year":"2015","journal-title":"Ultrasound. Med. Biol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1002\/ca.22788","article-title":"Application of Shear Wave Elastography for the Gastrocnemius Medial Head to Tennis Leg","volume":"30","author":"Yoshida","year":"2017","journal-title":"Clin. Anat."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Wang, C.-Z., Li, T.-J., and Zheng, Y.-P. (2014). Shear Modulus Estimation on Vastus Intermedius of Elderly and Young Females over the Entire Range of Isometric Contraction. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0101769"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3187","DOI":"10.1007\/s00330-020-07367-7","article-title":"Quantitative Evaluation of Passive Muscle Stiffness by Shear Wave Elastography in Healthy Individuals of Different Ages","volume":"31","author":"Liu","year":"2021","journal-title":"Eur. Radiol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1016\/j.exger.2006.10.007","article-title":"Aging Affects Passive Stiffness and Spindle Function of the Rat Soleus Muscle","volume":"42","author":"Rosant","year":"2007","journal-title":"Exp. Gerontol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"8274","DOI":"10.1038\/s41598-018-26574-3","article-title":"Associations of Passive Muscle Stiffness, Muscle Stretch Tolerance, and Muscle Slack Angle with Range of Motion: Individual and Sex Differences","volume":"8","author":"Miyamoto","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1385","DOI":"10.1152\/japplphysiol.90935.2008","article-title":"Effect of Estrogen on Tendon Collagen Synthesis, Tendon Structural Characteristics, and Biomechanical Properties in Postmenopausal Women","volume":"106","author":"Hansen","year":"2009","journal-title":"J. Appl. Physiol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.clinbiomech.2014.11.011","article-title":"Shear Wave Elastography of Passive Skeletal Muscle Stiffness: Influences of Sex and Age throughout Adulthood","volume":"30","author":"Eby","year":"2015","journal-title":"Clin. Biomech."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1016\/j.clinimag.2017.05.017","article-title":"Ultrasound Shear Wave Elastography in the Assessment of Passive Biceps Brachii Muscle Stiffness: Influences of Sex and Elbow Position","volume":"45","author":"Chen","year":"2017","journal-title":"Clin. Imaging"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1249\/00005768-199404000-00006","article-title":"Skeletal Muscle Weakness in Old Age: Underlying Mechanisms","volume":"26","author":"Brooks","year":"1994","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2080","DOI":"10.1249\/MSS.0000000000002024","article-title":"Muscle Stiffness of the Vastus Lateralis in Sprinters and Long-Distance Runners","volume":"51","author":"Miyamoto","year":"2019","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Csapo, R., Malis, V., Sinha, U., Du, J., and Sinha, S. (2014). Age-Associated Differences in Triceps Surae Muscle Composition and Strength\u2014An MRI-Based Cross-Sectional Comparison of Contractile, Adipose and Connective Tissue. BMC Musculoskelet. Disord., 15.","DOI":"10.1186\/1471-2474-15-209"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1096\/fj.14-262154","article-title":"Serum C1q as a Novel Biomarker of Sarcopenia in Older Adults","volume":"29","author":"Watanabe","year":"2015","journal-title":"FASEB J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"730","DOI":"10.1093\/gerona\/59.7.M730","article-title":"The Consequences of Resistance Training for Movement Control in Older Adults","volume":"59","author":"Barry","year":"2004","journal-title":"J. Gerontol. A Biol. Sci. Med. Sci."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1152\/jappl.2000.89.1.81","article-title":"Skeletal Muscle Mass and Distribution in 468 Men and Women Aged 18-88 Yr","volume":"89","author":"Janssen","year":"2000","journal-title":"J. Appl. Physiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1007\/s11357-013-9539-6","article-title":"Prevalence of Site-Specific Thigh Sarcopenia in Japanese Men and Women","volume":"36","author":"Abe","year":"2014","journal-title":"Age"}],"container-title":["International Journal of Environmental Research and Public Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/17\/8947\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:51:34Z","timestamp":1760165494000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/17\/8947"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,8,25]]},"references-count":25,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2021,9]]}},"alternative-id":["ijerph18178947"],"URL":"https:\/\/doi.org\/10.3390\/ijerph18178947","relation":{},"ISSN":["1660-4601"],"issn-type":[{"value":"1660-4601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,8,25]]}}}