{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T05:10:37Z","timestamp":1769577037435,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T00:00:00Z","timestamp":1769472000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PI19\/01490"],"award-info":[{"award-number":["PI19\/01490"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: In rotator cuff-related shoulder pain (RCRSP) without associated tendon rupture, therapeutic exercise is one of the main treatment strategies; however, the mechanisms through which it exerts its effects remain poorly understood. The aim of this study was to analyze the role of two potential mechanisms of action: increases in muscle strength and changes in the microarchitecture of the supraspinatus muscle. Methods: This prospective study included 39 patients with RCRSP treated with a strengthening exercise program. Muscle strength was assessed using dynamometry, and supraspinatus muscle stiffness was evaluated using shear wave elastography (SWE) at baseline and after 6 months of exercise. These measurements were correlated with clinical and perceived improvement in the patients. Results: Thirty-seven patients completed follow-up. At 6 months, 67.6% of participants reported being much better or fully recovered, 29.7% reported being somewhat better, and only one patient (2.7%) reported worsening. Overall, the increase in muscle strength was small. In participants reporting marked improvement or full recovery, strength gains were slightly greater, but a significant increase in supraspinatus muscle stiffness was observed. In contrast, participants with mild improvement or worsening showed smaller strength gains and no changes in muscle stiffness. Conclusions: Strength gains following strengthening exercises in RCRSP are small and of limited clinical relevance. In contrast, increased supraspinatus muscle stiffness assessed by SWE was observed after the exercise intervention and may reflect exercise-related adaptations; however, its biological meaning should be interpreted with caution.<\/jats:p>","DOI":"10.3390\/jcm15031015","type":"journal-article","created":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T15:41:56Z","timestamp":1769528516000},"page":"1015","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mechanism of Action of Therapeutic Exercise in Rotator Cuff Tendinopathy: What Does Elastography Add?"],"prefix":"10.3390","volume":"15","author":[{"given":"Irene","family":"P\u00e9rez-Porta","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"},{"name":"International Doctoral School, Universidad Rey Juan Carlos, 28933 Mostoles, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7687-8122","authenticated-orcid":false,"given":"Claudia","family":"de la Fuente-Escudero","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"\u00c1ngel","family":"Luis Bueno-Horcajadas","sequence":"additional","affiliation":[{"name":"Department of Radiology, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2726-8683","authenticated-orcid":false,"given":"Elia","family":"P\u00e9rez-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Statistics and Data Analysis Unit, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fernando","family":"Garc\u00eda-P\u00e9rez","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6554-2095","authenticated-orcid":false,"given":"Mar\u00eda","family":"Velasco-Arribas","sequence":"additional","affiliation":[{"name":"Research Unit, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mariano Tom\u00e1s","family":"Fl\u00f3rez-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Hospital Universitario Fundaci\u00f3n Alcorc\u00f3n, 28922 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lucas, J., Van Doorn, P., Hegedus, E., Lewis, J., and Van Der Windt, D. (2022). A systematic review of the global prevalence and incidence of shoulder pain. BMC Musculoskelet. Disord., 23.","DOI":"10.1186\/s12891-022-05973-8"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"pzaa229","DOI":"10.1093\/ptj\/pzaa229","article-title":"Understanding Shoulder Pain: A Qualitative Evidence Synthesis Exploring the Patient Experience","volume":"101","author":"Maxwell","year":"2020","journal-title":"Phys. Ther."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"100395","DOI":"10.1016\/j.bjpt.2022.100395","article-title":"International physical therapists consensus on clinical descriptors for diagnosing rotator cuff related shoulder pain: A Delphi study","volume":"26","author":"Lewis","year":"2022","journal-title":"Braz. J. Phys. Ther."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"451","DOI":"10.2519\/jospt.2025.13405","article-title":"What\u2019s in a Name? The Case for Using \u201cRotator Cuff\u2013Related Shoulder Pain\u201d in Clinical Practice","volume":"55","author":"Lewis","year":"2025","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"235","DOI":"10.2519\/jospt.2025.13182","article-title":"Rotator Cuff Tendinopathy Diagnosis, Nonsurgical Medical Care, and Rehabilitation: A Clinical Practice Guideline","volume":"55","author":"Desmeules","year":"2025","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1233","DOI":"10.1016\/j.apmr.2019.12.017","article-title":"Shoulder Rotator Cuff Disorders: A Systematic Review of Clinical Practice Guidelines and Semantic Analyses of Recommendations","volume":"101","author":"Lafrance","year":"2020","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e1879","DOI":"10.1002\/msc.1879","article-title":"Is exercise therapy the right treatment for rotator cuff-related shoulder pain? Uncertainties, theory, and practice","volume":"22","author":"Powell","year":"2024","journal-title":"Musculoskelet. Care"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"102646","DOI":"10.1016\/j.msksp.2022.102646","article-title":"\u201cYou have (rotator cuff related) shoulder pain, and to treat it, I recommend exercise.\u201d A scoping review of the possible mechanisms underpinning exercise therapy","volume":"62","author":"Powell","year":"2022","journal-title":"Musculoskelet. Sci. Pract."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1822","DOI":"10.1016\/j.apmr.2020.06.013","article-title":"The Efficacy of Higher Versus Lower Dose Exercise in Rotator Cuff Tendinopathy: A Systematic Review of Randomized Controlled Trials","volume":"101","author":"Malliaras","year":"2020","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3040","DOI":"10.1177\/03635465211016008","article-title":"Effectiveness of Adding a Large Dose of Shoulder Strengthening to Current Nonoperative Care for Subacromial Impingement: A Pragmatic, Double-Blind Randomized Controlled Trial (SExSI Trial)","volume":"49","author":"Clausen","year":"2021","journal-title":"Am. J. Sports Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"pzaf107","DOI":"10.1093\/ptj\/pzaf107","article-title":"Relationship Between Tendon Tissue and Shoulder Disability Change During an 8-Week Exercise Intervention for Rotator Cuff Tendinopathy: An Observational Study","volume":"105","author":"Heindel","year":"2025","journal-title":"Phys. Ther."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1016\/j.jbmt.2009.06.004","article-title":"Clinical and MRI findings after high dosage medical exercise therapy in patients with long lasting subacromial pain syndrome: A case series on six patients","volume":"14","author":"Myhr","year":"2010","journal-title":"J. Bodyw. Mov. Ther."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2325967120965185","DOI":"10.1177\/2325967120965185","article-title":"Strain Elastography and Tendon Response to an Exercise Program in Patients With Supraspinatus Tendinopathy: An Exploratory Study","volume":"8","author":"Brage","year":"2020","journal-title":"Orthop. J. Sports Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2977","DOI":"10.12998\/wjcc.v8.i14.2977","article-title":"Role of shear wave elastography in the evaluation of the treatment and prognosis of supraspinatus tendinitis","volume":"8","author":"Zhou","year":"2020","journal-title":"World J. Clin. Cases"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3853","DOI":"10.1016\/j.jbiomech.2015.09.038","article-title":"Quantitative assessment of rotator cuff muscle elasticity: Reliability and feasibility of shear wave elastography","volume":"48","author":"Hatta","year":"2015","journal-title":"J. Biomech."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"P\u00e9rez-Porta, I., Garc\u00eda-P\u00e9rez, F., P\u00e9rez-Manzanero, M.\u00c1., Urraca-Gesto, M.A., Araujo-Narv\u00e1ez, A., Velasco-Arribas, M., Navarro-Santana, M.J., Plaza-Manzano, G., P\u00e9rez-Fern\u00e1ndez, E., and Fl\u00f3rez-Garc\u00eda, M.T. (2025). Adding Multimedia Animations to Exercise Therapy Provides No Additional Benefit for Rotator Cuff\u2013Related Shoulder Pain: A Randomized Clinical Trial. J. Clin. Med., 14.","DOI":"10.3390\/jcm14227964"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"e085381","DOI":"10.1136\/bmjopen-2024-085381","article-title":"Effects of a web application based on multimedia animations to support therapeutic exercise for rotator cuff-related shoulder pain: Protocol for an open-label randomised controlled trial","volume":"14","year":"2024","journal-title":"BMJ Open"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1276","DOI":"10.1097\/01.blo.0000533628.06091.0a","article-title":"Can Shoulder Muscle Activity Be Evaluated With Ultrasound Shear Wave Elastography?","volume":"476","author":"Kim","year":"2018","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1148\/radiol.2015150908","article-title":"Quantitative Shear-Wave US Elastography of the Supraspinatus Muscle: Reliability of the Method and Relation to Tendon Integrity and Muscle Quality","volume":"278","author":"Rosskopf","year":"2016","journal-title":"Radiology"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1787","DOI":"10.1080\/02640414.2019.1594570","article-title":"Validity and reliability of a low-cost dynamometer to assess maximal isometric strength of upper limb: Low cost dynamometry and isometric strength of upper limb","volume":"37","year":"2019","journal-title":"J. Sports Sci."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"P\u00e9rez-Porta, I., Bueno-Horcajadas, \u00c1.L., Garc\u00eda-P\u00e9rez, F., Mart\u00ednez-Ponce, D.C., Corrales-Mantec\u00f3n, S., Fl\u00f3rez-Garc\u00eda, M.T., and Velasco-Arribas, M. (2025). Normative Data of Supraspinatus Muscle Shear Wave Elastography in Healthy Shoulders: A Cross-Sectional Study. J. Clin. Med., 14.","DOI":"10.3390\/jcm14041121"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"102307","DOI":"10.1016\/j.msksp.2020.102307","article-title":"Why is exercise prescribed for people with chronic low back pain? A review of the mechanisms of benefit proposed by clinical trialists","volume":"51","author":"Wun","year":"2021","journal-title":"Musculoskelet. Sci. Pract."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e003220","DOI":"10.1136\/rmdopen-2023-003220","article-title":"Mechanisms of action of therapeutic exercise for knee and hip OA remain a black box phenomenon: An individual patient data mediation study with the OA Trial Bank","volume":"9","author":"Runhaar","year":"2023","journal-title":"RMD Open"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Powell, J., Wood, L., Cashin, A.G., and Lewis, J.S. (2025). It is not all about strength: Rethinking mechanistic assumptions in exercise-based rehabilitation for musculoskeletal pain relief. Br. J. Sports Med.","DOI":"10.1136\/bjsports-2025-110372"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"319","DOI":"10.2519\/jospt.1994.20.6.319","article-title":"The Effect of Medical Exercise Therapy on a Patient With Chronic Supraspinatus Tendinitis. Diagnostic Ultrasound\u2014Tissue Regeneration: A Case Study","volume":"20","author":"Torstensen","year":"1994","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"23259671241280192","DOI":"10.1177\/23259671241280192","article-title":"Clinical Outcomes and Tendon Structure at 3- to 4-Year Follow-up After Exercise-Based Treatment of Patellar Tendinopathy: A Prospective Study","volume":"12","author":"Agergaard","year":"2024","journal-title":"Orthop. J. Sports Med."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"458","DOI":"10.1016\/j.jsams.2024.12.006","article-title":"Do physical or imaging changes explain the effectiveness of progressive tendon loading exercises? A causal mediation analysis of athletes with patellar tendinopathy","volume":"28","author":"Deng","year":"2025","journal-title":"J. Sci. Med. Sport"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"708","DOI":"10.1097\/PHM.0000000000000951","article-title":"Clinical Improvements Are Not Explained by Changes in Tendon Structure on Ultrasound Tissue Characterization After an Exercise Program for Patellar Tendinopathy","volume":"97","author":"Rio","year":"2018","journal-title":"Am. J. Phys. Med. Rehabil."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1918","DOI":"10.1016\/j.jse.2024.03.055","article-title":"Do therapeutic exercises impact supraspinatus tendon thickness? Secondary analyses of the combined dataset from two randomized controlled trials in patients with rotator cuff-related shoulder pain","volume":"33","author":"Ingwersen","year":"2024","journal-title":"J. Shoulder Elb. Surg."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"100934","DOI":"10.1016\/j.jtv.2025.100934","article-title":"The effect of core exercises on shoulder rotator strength, core endurance and suprasipinatus structure in tennis players with rotator cuff injuries","volume":"34","author":"Ersever","year":"2025","journal-title":"J. Tissue Viability"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1051","DOI":"10.2214\/AJR.21.27129","article-title":"Utility of Preoperative Shear-Wave Elastography of the Supraspinatus Muscle for Predicting Successful Rotator Cuff Repair: A Prospective Observational Study With MRI Correlation","volume":"218","author":"Jeong","year":"2022","journal-title":"Am. J. Roentgenol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1937","DOI":"10.1002\/jum.16528","article-title":"Prospective Evaluation of Normal Supraspinatus Muscle Using Shear Wave Elastography: Comparison With Symptomatic Tendon Tears","volume":"43","author":"Jeong","year":"2024","journal-title":"J. Ultrasound Med."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e17696","DOI":"10.1016\/j.heliyon.2023.e17696","article-title":"Regional assessments of supraspinatus muscle stiffness in normal adults using shear wave elastography","volume":"9","author":"Jiang","year":"2023","journal-title":"Heliyon"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"pzaf006","DOI":"10.1093\/ptj\/pzaf006","article-title":"Effectiveness of Additional or Standalone Corticosteroid Injections Compared to Physical Therapist Interventions in Rotator Cuff Tendinopathy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials","volume":"105","author":"Lazzarini","year":"2025","journal-title":"Phys. Ther."},{"key":"ref_35","first-page":"e48907","article-title":"Manual Therapy and Exercise Have Similar Outcomes to Corticosteroid Injections in the Management of Patients With Subacromial Pain Syndrome: A Systematic Review and Meta-Analysis","volume":"15","author":"Karanasios","year":"2023","journal-title":"Cureus"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Lin, C.-Y., Huang, S.-C., Tzou, S.-J., Yin, C.-H., Chen, J.-S., Chen, Y.-S., and Chang, S.-T. (2022). A Positive Correlation between Steroid Injections and Cuff Tendon Tears: A Cohort Study Using a Clinical Database. Int. J. Environ. Res. Public Health, 19.","DOI":"10.3390\/ijerph19084520"}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/3\/1015\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T16:00:36Z","timestamp":1769529636000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/3\/1015"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,27]]},"references-count":36,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["jcm15031015"],"URL":"https:\/\/doi.org\/10.3390\/jcm15031015","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,27]]}}}