{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,2]],"date-time":"2026-11-02T16:30:32Z","timestamp":1793637032800,"version":"4.5.1"},"reference-count":29,"publisher":"Human Kinetics","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,11,1]]},"abstract":"<jats:p>Ramadan fasting can alter hydration, sleep, and training schedules in competitive swimmers aged 6\u201320\u00a0years, but evidence in swimmers is limited. This prospective cohort study investigated within-participant changes in bioelectrical impedance analysis and body composition across Ramadan in swimmers. Swimmers were assessed at 3 time points: approximately 7\u00a0days before the first day of Ramadan, during the third week of Ramadan, and approximately 14\u00a0days after Ramadan ended. Participants were 52 competitive swimmers aged 6\u201320\u00a0years (39 males). Phase-sensitive single-frequency bioelectrical impedance analysis (50\u00a0kHz) measured phase angle (A50) and resistance (R50); derived outcomes included fat-free mass, fat mass, and body mass index. Linear mixed-effects models adjusted for age and sex estimated changes versus baseline with false discovery rate control. R50 increased during (+50 \u03a9) and after Ramadan (+42 \u03a9), fat-free mass decreased (\u22121.86\u00a0kg and \u22121.41\u00a0kg), fat mass increased (+1.29\u00a0kg and +1.68\u00a0kg), A50 declined modestly after Ramadan (\u22120.38\u00b0), and body mass index showed no clear change. Effects were directionally consistent across sex and fasting-type subgroups. Across Ramadan, swimmers aged 6\u201320\u00a0years exhibited higher electrical resistance and unfavorable shifts in body composition despite stable body mass index, consistent with transient hydration\/cellular stress and possible tissue-related changes that cannot be confirmed without functional or regional measures. Routine bioelectrical impedance analysis-based monitoring and targeted evening hydration, protein distribution, and light resistance training may help preserve fat-free mass during Ramadan.<\/jats:p>","DOI":"10.1123\/pes.2025-0145","type":"journal-article","created":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T01:29:43Z","timestamp":1791336583000},"page":"454-461","source":"Crossref","is-referenced-by-count":0,"title":["Bioimpedance-Derived Hydration and Body Composition Shifts Across Ramadan in Competitive Swimmers Aged 6\u201320\u00a0Years: A Prospective Cohort Study"],"prefix":"10.1123","volume":"38","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8981-0100","authenticated-orcid":true,"given":"Ana","family":"Anjos","sequence":"first","affiliation":[{"name":"Physiotherapy Department, Fatima College of Health Science, Abu Dhabi, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1377-5318","authenticated-orcid":true,"given":"Etienne","family":"Gouraud","sequence":"additional","affiliation":[{"name":"Research and Development Department, Aminogram SAS, La Ciotat, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-4388-4305","authenticated-orcid":true,"given":"Mohammed","family":"Al Musaabi","sequence":"additional","affiliation":[{"name":"Pediatric Emergency Department, Sheikh Shakhbout Medical City (SSMC), Abu Dhabi, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6230-1595","authenticated-orcid":true,"given":"Ibrahim","family":"Alzaabi","sequence":"additional","affiliation":[{"name":"Pediatric Emergency Department, Sheikh Shakhbout Medical City (SSMC), Abu Dhabi, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2314-5088","authenticated-orcid":true,"given":"Nuno","family":"Miguel Goncalves","sequence":"additional","affiliation":[{"name":"Rehabilitation Department, German Dental & Neuromuscular Clinic, Dubai, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-0524-5578","authenticated-orcid":true,"given":"Nour","family":"Al Mheiri","sequence":"additional","affiliation":[{"name":"Allied Health Department, M42, Abu Dhabi, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3722-4342","authenticated-orcid":true,"given":"Sunitha","family":"Mysore","sequence":"additional","affiliation":[{"name":"Physiotherapy Department, Fatima College of Health Science, Abu Dhabi, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-8519-511X","authenticated-orcid":true,"given":"Abdulla","family":"Al Rahoomi","sequence":"additional","affiliation":[{"name":"Physical Medicine & Rehabilitation Department, College of Medicine & Health Sciences, United Arab Emirates University, Abu Dhabi, United Arab Emirates"},{"name":"Physical Medicine & Rehabilitation Department, College of Medicine & Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates"},{"name":"Physical Medicine & Rehabilitation Department, Sheikh Tahnoon Medical City, Al Ain, United Arab Emirates"},{"name":"Physical Medicine & Rehabilitation Department, UAE National Olympics Sports Medicine Committee, Dubai, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"100","reference":[{"issue":"Suppl 1","key":"r1","series-title":"J Pak Med Assoc","first-page":"S6","article-title":"Physiological changes during fasting in Ramadan","volume":"65","author":"Meo SA","year":"2015","unstructured":"Meo SA, Hassan A. 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