{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T18:20:08Z","timestamp":1787682008692,"version":"build-2784847793"},"reference-count":26,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:00:00Z","timestamp":1787616000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    Whether height-based normalization indices for appendicular lean mass (ALM) are metabolically neutral remains uncertain, because such indices may be influenced by\u00a0adiposity. We evaluated ALM normalized to trunk lean mass (ALM\/TLM) \u2014 both with bone mineral content excluded \u2014 as a normalization strategy potentially less susceptible to adiposity-related distortion. Using the Korea National Health and Nutrition Examination Survey 2008\u20132010, we analyzed 3,176 adults aged \u226565 years (1,373 men; 1,803 women) for body composition by dual-energy X-ray absorptiometry. Sex-specific Class I and Class II cut-offs were derived from a healthy young reference group aged 20\u201339 years (n\u2009=\u20093,727) at 1 SD and 2 SD below the young-adult mean. Metabolic syndrome (MetS) was defined by NCEP-ATP III criteria with population-specific waist cut-offs. Survey-weighted regression models were adjusted for age, smoking, alcohol, and physical activity. The appendicular skeletal muscle mass index (ASMI; ALM\/height\n                    <jats:sup>2<\/jats:sup>\n                    ) correlated positively with fat mass index (FMI) (men r=+0.288; women r=+0.358; both p\u2009&lt;\u20090.001), whereas ALM\/TLM correlated negatively with FMI (men r=\u22120.199; women r=\u22120.243; both p\u2009&lt;\u20090.001). ASMI Class I low muscle mass showed an inverse association with MetS (men odds ratio [OR] 0.496, 95% confidence interval [CI] 0.388\u20130.636; women OR 0.475, 95% CI 0.328\u20130.686). In contrast, ALM\/TLM Class II showed positive associations with MetS (men OR 2.779, 95% CI 2.074\u20133.722; women OR 2.701, 95% CI 1.680\u20134.340; both p\u2009&lt;\u20090.001). The inverse ALM\/TLM\u2013HOMA-IR association persisted after FMI adjustment (men \u03b2=\u22120.131, p\u2009&lt;\u20090.001; women \u03b2=\u22120.065, p\u2009=\u20090.007). ASMI correlated positively with adiposity, while ASMI-defined low muscle mass was inversely associated with MetS, suggesting that ASMI may partly reflect body size\/adiposity rather than relative muscle depletion alone; this inverse association should not be interpreted as protective. By contrast, ALM\/TLM-defined low muscle mass showed consistently positive associations with MetS across adiposity strata, supporting further evaluation of ALM\/TLM, although its clinical validity remains unestablished.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0357017","type":"journal-article","created":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T17:34:52Z","timestamp":1787679292000},"page":"e0357017","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Appendicular-to-trunk lean mass ratio resolves the height-based normalization paradox in low muscle mass and metabolic syndrome: A population-based cross-sectional study"],"prefix":"10.1371","volume":"21","author":[{"given":"Jung Ah","family":"Lim","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sung Hoon","family":"Yu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jung Hwan","family":"Park","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shinje","family":"Moon","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chang Beom","family":"Lee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8535-0565","authenticated-orcid":true,"given":"Sangmo","family":"Hong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,25]]},"reference":[{"key":"pone.0357017.ref001","article-title":"Skeletal muscle insulin resistance is the primary defect in type 2 diabetes","author":"RA DeFronzo","year":"2009","journal-title":"Diabetes Care"},{"issue":"16","key":"pone.0357017.ref002","doi-asserted-by":"crossref","DOI":"10.1172\/JCI158451","article-title":"Metabolic changes in aging humans: current evidence and therapeutic strategies","volume":"132","author":"AK Palmer","year":"2022","journal-title":"J Clin Invest"},{"issue":"7","key":"pone.0357017.ref003","doi-asserted-by":"crossref","first-page":"1477","DOI":"10.1007\/s40520-023-02427-6","article-title":"Higher abdominal adiposity is associated with higher lean muscle mass but lower muscle quality in middle-aged and older men and women: the Framingham Heart Study","volume":"35","author":"R Raghupathy","year":"2023","journal-title":"Aging Clin Exp Res"},{"issue":"1","key":"pone.0357017.ref004","doi-asserted-by":"crossref","DOI":"10.1002\/jcsm.13714","article-title":"Fat-free mass: friend or foe to metabolic health?","volume":"16","author":"CJ Oliver","year":"2025","journal-title":"J Cachexia Sarcopenia Muscle"},{"issue":"1","key":"pone.0357017.ref005","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1002\/jcsm.12856","article-title":"Increased odds of having the metabolic syndrome with greater fat-free mass: counterintuitive results from the National Health and Nutrition Examination Survey database","volume":"13","author":"J-C Lagac\u00e9","year":"2022","journal-title":"J Cachexia Sarcopenia Muscle"},{"issue":"2","key":"pone.0357017.ref006","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1002\/jcsm.12520","article-title":"A counterintuitive perspective for the role of fat-free mass in metabolic health","volume":"11","author":"J-C Lagac\u00e9","year":"2020","journal-title":"J Cachexia Sarcopenia Muscle"},{"issue":"12","key":"pone.0357017.ref007","doi-asserted-by":"crossref","first-page":"2271","DOI":"10.1016\/j.numecd.2020.07.036","article-title":"Comparison of the associations between appendicular lean mass adjustment methods and cardiometabolic factors","volume":"30","author":"Y-M Song","year":"2020","journal-title":"Nutr Metab Cardiovasc Dis"},{"issue":"1","key":"pone.0357017.ref008","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1038\/s41598-018-37347-3","article-title":"Comparisons of different indices of low muscle mass in relationship with cardiometabolic disorder","volume":"9","author":"JY Kim","year":"2019","journal-title":"Sci Rep"},{"issue":"1","key":"pone.0357017.ref009","doi-asserted-by":"crossref","first-page":"2590","DOI":"10.1038\/s41598-023-29827-y","article-title":"Total and regional appendicular skeletal muscle mass prediction from dual-energy X-ray absorptiometry body composition models","volume":"13","author":"C McCarthy","year":"2023","journal-title":"Sci Rep"},{"issue":"2","key":"pone.0357017.ref010","article-title":"Organ-tissue mass measurement allows modeling of REE and metabolically active tissue mass","volume":"275","author":"D Gallagher","year":"1998","journal-title":"Am J Physiol"},{"issue":"1","key":"pone.0357017.ref011","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1093\/ije\/dyt228","article-title":"Data resource profile: the Korea National Health and Nutrition Examination Survey (KNHANES)","volume":"43","author":"S Kweon","year":"2014","journal-title":"Int J Epidemiol"},{"issue":"19","key":"pone.0357017.ref012","doi-asserted-by":"crossref","first-page":"2486","DOI":"10.1001\/jama.285.19.2486","article-title":"Executive Summary of The Third Report of The National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, And Treatment of High Blood Cholesterol In Adults (Adult Treatment Panel III)","volume":"285","author":"Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults","year":"2001","journal-title":"JAMA"},{"issue":"4","key":"pone.0357017.ref013","doi-asserted-by":"crossref","first-page":"418","DOI":"10.3803\/EnM.2014.29.4.418","article-title":"Optimal waist circumference cutoff values for the diagnosis of abdominal obesity in korean adults","volume":"29","author":"YS Yoon","year":"2014","journal-title":"Endocrinol Metab (Seoul)"},{"issue":"7","key":"pone.0357017.ref014","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1007\/BF00280883","article-title":"Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man","volume":"28","author":"DR Matthews","year":"1985","journal-title":"Diabetologia"},{"issue":"9","key":"pone.0357017.ref015","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0007038","article-title":"Dual energy X-Ray absorptiometry body composition reference values from NHANES","volume":"4","author":"TL Kelly","year":"2009","journal-title":"PLoS One"},{"issue":"12","key":"pone.0357017.ref016","doi-asserted-by":"crossref","first-page":"1599","DOI":"10.3346\/jkms.2011.26.12.1599","article-title":"Characteristics of body fat, body fat percentage and other body composition for Koreans from KNHANES IV","volume":"26","author":"S Hong","year":"2011","journal-title":"J Korean Med Sci"},{"issue":"6","key":"pone.0357017.ref017","doi-asserted-by":"crossref","first-page":"1580","DOI":"10.1002\/jcsm.12613","article-title":"Validation of a description of sarcopenic obesity defined as excess adiposity and low lean mass relative to adiposity","volume":"11","author":"JF Baker","year":"2020","journal-title":"J Cachexia Sarcopenia Muscle"},{"issue":"5","key":"pone.0357017.ref018","doi-asserted-by":"crossref","first-page":"576","DOI":"10.1093\/gerona\/glu012","article-title":"Criteria for clinically relevant weakness and low lean mass and their longitudinal association with incident mobility impairment and mortality: the foundation for the National Institutes of Health (FNIH) sarcopenia project","volume":"69","author":"RR McLean","year":"2014","journal-title":"J Gerontol A Biol Sci Med Sci"},{"issue":"5","key":"pone.0357017.ref019","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1159\/000540219","article-title":"Central Lean Mass Distribution and the Risks of All-Cause and Cause-Specific Mortality in 40,283 UK Biobank Participants","volume":"17","author":"L Ding","year":"2024","journal-title":"Obes Facts"},{"key":"pone.0357017.ref020","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/j.clnu.2025.02.001","article-title":"Dual-energy x-ray absorptiometry derived body composition trajectories across adulthood: Reference values and associations with body roundness index and body mass index","volume":"46","author":"J Pratt","year":"2025","journal-title":"Clin Nutr"},{"key":"pone.0357017.ref021","doi-asserted-by":"crossref","first-page":"1724047","DOI":"10.3389\/fphys.2025.1724047","article-title":"Influence of passive, diet-based, hydration on muscle quantity assessment","volume":"16","author":"JS Viken","year":"2025","journal-title":"Front Physiol"},{"issue":"10","key":"pone.0357017.ref022","doi-asserted-by":"crossref","first-page":"2430","DOI":"10.1016\/j.clnu.2024.09.028","article-title":"Trunk-to-leg volume and appendicular lean mass from a commercial 3-dimensional optical body scanner for disease risk identification","volume":"43","author":"JP Bennett","year":"2024","journal-title":"Clin Nutr"},{"issue":"4","key":"pone.0357017.ref023","doi-asserted-by":"crossref","first-page":"990","DOI":"10.1016\/j.clnu.2021.11.014","article-title":"Definition and diagnostic criteria for sarcopenic obesity: ESPEN and EASO consensus statement","volume":"41","author":"LM Donini","year":"2022","journal-title":"Clin Nutr"},{"issue":"1","key":"pone.0357017.ref024","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1093\/ageing\/afy169","article-title":"Sarcopenia: revised European consensus on definition and diagnosis","volume":"48","author":"AJ Cruz-Jentoft","year":"2019","journal-title":"Age Ageing"},{"issue":"11","key":"pone.0357017.ref025","doi-asserted-by":"crossref","first-page":"2164","DOI":"10.1038\/s43587-025-01004-y","article-title":"A focus shift from sarcopenia to muscle health in the Asian Working Group for Sarcopenia 2025 Consensus Update","volume":"5","author":"L-K Chen","year":"2025","journal-title":"Nat Aging"},{"issue":"6","key":"pone.0357017.ref026","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.2337\/diacare.27.6.1487","article-title":"Use and abuse of HOMA modeling","volume":"27","author":"TM Wallace","year":"2004","journal-title":"Diabetes Care"}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0357017","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T17:34:58Z","timestamp":1787679298000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0357017"}},"subtitle":[],"editor":[{"given":"Girish C","family":"Melkani","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,8,25]]},"references-count":26,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8,25]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0357017","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,25]]}}}