{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T07:57:32Z","timestamp":1791359852627,"version":"4.3.1"},"reference-count":57,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,10,26]],"date-time":"2022-10-26T00:00:00Z","timestamp":1666742400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF)","award":["2021M3I2A1077405"],"award-info":[{"award-number":["2021M3I2A1077405"]}]},{"name":"Life Cycle Nutrition Research Center, Ildong Foodis Co., Ltd. (Seoul, Korea)","award":["2021M3I2A1077405"],"award-info":[{"award-number":["2021M3I2A1077405"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Although sarcopenia has been dealt with in several studies, the standardized guidelines for preventing sarcopenia resulting from increased life expectancy are still insufficient. Therefore, this study evaluated the effects of daily resistance exercise and the intake of leucine-rich protein supplements daily for 12 weeks on the body composition and physical function of healthy adults aged &gt;50 years living in Korea. The study analyzed 50 healthy people without medical conditions, who were randomly assigned to two groups (taking either protein powder or placebo powder) twice a day for 12 weeks. All participants performed resistance exercises regularly that could be repeated 8\u201312 times using a TheraBand for 12 weeks. A total of 41 participants completed the study. When measured via bioimpedance analysis (BIA), body fat mass (kg) and body fat (%) significantly decreased, and lean body mass (LBM) (kg) and skeletal muscle mass (SMM) (kg) significantly increased, in both groups. However, when measured via dual-energy X-ray absorptiometry (DXA), LBM was significantly increased only in the protein powder group. The LBM and SMM change measured via BIA was significantly greater in the protein powder group than in the placebo powder group (LBM: 0.95 \u00b1 0.91 kg in the protein powder group vs. 0.38 \u00b1 1.06 kg in the placebo powder group, p = 0.043; SMM: 0.69 \u00b1 0.58 kg in the protein powder group vs. 0.29 \u00b1 0.65 kg in the placebo powder group, p = 0.039, respectively). In the senior fitness test (SFT), significant functional improvement was found within the two groups, but no significant difference was found between the groups in the degree of improvement. In conclusion, in older people aged &gt;50, to prevent sarcopenia, is more effective to combine resistance exercise and leucine-rich protein supplementation than to simply perform resistance exercise.<\/jats:p>","DOI":"10.3390\/nu14214501","type":"journal-article","created":{"date-parts":[[2022,10,26]],"date-time":"2022-10-26T09:59:37Z","timestamp":1666778377000},"page":"4501","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Effect of Intake of Leucine-Rich Protein Supplement in Parallel with Resistance Exercise on the Body Composition and Function of Healthy Adults"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8923-6260","authenticated-orcid":false,"given":"Gyu Seok","family":"Oh","sequence":"first","affiliation":[{"name":"Department of Rehabilitation Medicine, Gil Medical Center, Incheon 21565, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ju-hak","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Human Movement Science, Incheon National University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyunghee","family":"Byun","sequence":"additional","affiliation":[{"name":"Functional Cellular Networks Laboratory, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 13120, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4434-799X","authenticated-orcid":false,"given":"Dong-Il","family":"Kim","sequence":"additional","affiliation":[{"name":"Division of Health and Kinesiology, Incheon National University, Incheon 21999, Korea"},{"name":"Sports Functional Disability Institute, Incheon National University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1684-4737","authenticated-orcid":false,"given":"Ki Deok","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Gil Medical Center, Gachon University College of Medicine, Incheon 21565, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,26]]},"reference":[{"key":"ref_1","first-page":"412","article-title":"European Working Group on Sarcopenia in Older People: Sarcopenia: European consensus on definition and diagnosis. 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