{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T17:02:58Z","timestamp":1773939778080,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T00:00:00Z","timestamp":1773878400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFMK"],"abstract":"<jats:p>Background: Type 2 diabetes mellitus (T2DM) is linked to accelerated losses in muscle function. The aim of the present investigation was to evaluate the effect of chronic higher-protein intake on isokinetic knee performance in the older adults with type 2 diabetes mellitus (T2DM). Methods: Thirty adults (15 men and 15 women) aged 60\u201380 years with non-insulin-treated T2DM and sarcopenia-related deficits were randomized for 12 weeks to a higher-protein diet (1.2\u20131.5 g\u00b7kg\u22121\u00b7day\u22121) or a recommended protein diet (0.8\u20131.0 g\u00b7kg\u22121\u00b7day\u22121), with meal plans designed to maintain body mass. Protein was increased mainly through Mediterranean-style protein sources while diet was monitored using repeated 3-day recalls. Isokinetic knee extensors and flexors peak torque (angular velocity 60\u00b0\/s) was assessed at baseline and at week 6 and at the end of the 12th week of intervention. Fatigability (20 maximal contractions at an angular velocity at 180\u00b0\/s) and DXA body composition were assessed at baseline and at the end of the 12th week of intervention. Data were analyzed using two-way repeated-measures ANOVA with repeated measures on time (2 groups \u00d7 3 time points), followed by post hoc analysis when significant difference was occurred. Results: Thirty participants completed the trial. Energy intake and body mass remained stable in both groups. At the end of week 12, peak torque declined in the control group (p &lt; 0.05) but remained stable in the higher-protein group. The fatigue index worsened over time in controls but was preserved in the higher protein group, resulting in a significant group d7 time interaction at week 12 (p &lt; 0.05) (post hoc between-group difference at week 12, p &lt; 0.05). Fat-free mass and blood pressure did not change. In fat mass, a decrease was observed with higher protein intake, whereas it remained stable in the control group. Conclusions: Higher protein intake for 12 weeks preserved knee muscle performance in older adults with T2DM without weight gain, supporting dietary protein optimization to counter functional decline.<\/jats:p>","DOI":"10.3390\/jfmk11010125","type":"journal-article","created":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T15:38:01Z","timestamp":1773934681000},"page":"125","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of Higher Dietary Protein Intake on Isokinetic Muscle Performance in Older Adults with Type 2 Diabetes Mellitus"],"prefix":"10.3390","volume":"11","author":[{"given":"Stavroula","family":"Kalyva","sequence":"first","affiliation":[{"name":"School of Physical Education and Sport Science, National and Kapodistrian University of Athens, 17237 Athens, Greece"},{"name":"Sports Excellence, 1st Orthopedics Department, School of Health Sciences, National and Kapodistrian University of Athens, 12462 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dionysia","family":"Argyropoulou","sequence":"additional","affiliation":[{"name":"School of Physical Education and Sport Science, National and Kapodistrian University of Athens, 17237 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7890-2720","authenticated-orcid":false,"given":"Panagiotis","family":"Koulouvaris","sequence":"additional","affiliation":[{"name":"Sports Excellence, 1st Orthopedics Department, School of Health Sciences, National and Kapodistrian University of Athens, 12462 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7356-6027","authenticated-orcid":false,"given":"Charilaos","family":"Tsolakis","sequence":"additional","affiliation":[{"name":"School of Physical Education and Sport Science, National and Kapodistrian University of Athens, 17237 Athens, Greece"},{"name":"Sports Excellence, 1st Orthopedics Department, School of Health Sciences, National and Kapodistrian University of Athens, 12462 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0049-5395","authenticated-orcid":false,"given":"Gerasimos","family":"Terzis","sequence":"additional","affiliation":[{"name":"School of Physical Education and Sport Science, National and Kapodistrian University of Athens, 17237 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0536-6397","authenticated-orcid":false,"given":"Tzortzis","family":"Nomikos","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Dietetics, Harokopio University, 17676 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nickos D.","family":"Geladas","sequence":"additional","affiliation":[{"name":"School of Physical Education and Sport Science, National and Kapodistrian University of Athens, 17237 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9225-8177","authenticated-orcid":false,"given":"Anastasios A.","family":"Theodorou","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, School of Sciences, European University Cyprus, 2404 Nicosia, Cyprus"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9469-0457","authenticated-orcid":false,"given":"Vassilis","family":"Paschalis","sequence":"additional","affiliation":[{"name":"School of Physical Education and Sport Science, National and Kapodistrian University of Athens, 17237 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"American Diabetes Association Professional Practice Committee (2024). 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