{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T15:07:34Z","timestamp":1780672054532,"version":"3.54.1"},"reference-count":23,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T00:00:00Z","timestamp":1780531200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background\/Objectives: Body water, including its distribution between the intracellular (ICW) and extracellular (ECW) compartments, plays an important role in skeletal muscle physiology. The aim of this study was to assess whether body water distribution indices, namely ECW\/ICW and ECW\/TBW, differ according to age and sex, and whether they are associated with skeletal muscle index (SMI) after adjustment for BMI, age, and sex. Methods: The study included 188 healthy individuals: 71 older women (71.6 \u00b1 6.4 years), 37 older men (72.7 \u00b1 4.7 years), 40 female students (22.5 \u00b1 0.9 years), and 40 male students (22.8 \u00b1 1.8 years). Body composition was assessed using a Tanita MC-780 bioimpedance analyser. The ECW\/ICW and ECW\/TBW ratios were calculated. Nonparametric analyses, Kendall\u2019s rank correlations, and linear regression models adjusted for BMI, age, and sex were used. Results: Older adults had significantly higher ECW\/ICW and ECW\/TBW values than younger participants, and women had higher values than men within the same age groups. Both indices correlated positively with age and BMI, and negatively with SMI. In multivariate models, ECW\/TBW remained negatively associated with SMI after adjustment. BMI and male sex correlated positively with SMI, whereas age was not a significant predictor. Conclusions: Body water distribution indices (ECW\/ICW, ECW\/TBW) reflect age- and sex-related differences in water distribution and correlate with SMI independently of BMI, age, and sex. They may serve as complementary markers of skeletal muscle ageing.<\/jats:p>","DOI":"10.3390\/nu18111818","type":"journal-article","created":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T17:11:04Z","timestamp":1780593064000},"page":"1818","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Water Distribution in the Body as a Source of Information on Markers of Skeletal Muscle Ageing"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1533-0291","authenticated-orcid":false,"given":"Anna","family":"Skrzek","sequence":"first","affiliation":[{"name":"Faculty of Physiotherapy, Department of Physiotherapy in Movment System Dysfunctions and Kinesiology, University of Health and Sports Science in Wroc\u0142aw, 51-612 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7522-4058","authenticated-orcid":false,"given":"Ma\u0142gorzata","family":"S\u0142owinska-Lisowska","sequence":"additional","affiliation":[{"name":"Faculty of Physical Education and Sport, Department of Biological Pronciples of Physical Activity, University of Health and Sports Science in Wroc\u0142aw, 51-612 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7005-3018","authenticated-orcid":false,"given":"Agnieszka","family":"D\u0119biec-B\u0105k","sequence":"additional","affiliation":[{"name":"Faculty of Physiotherapy, Department of Physiotherapy in Movment System Dysfunctions and Kinesiology, University of Health and Sports Science in Wroc\u0142aw, 51-612 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7408-3078","authenticated-orcid":false,"given":"Agnieszka Matylda","family":"Schlichtinger","sequence":"additional","affiliation":[{"name":"Faculty of Finance and Management, WSB Merito University in Wroc\u0142aw, 53-609 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1007\/s12603-018-1129-y","article-title":"Total Body Water and Intracellular Water Relationships with Muscle Strength, Frailty and Functional Performance in an Elderly Population. 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