{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T08:38:28Z","timestamp":1769503108961,"version":"3.49.0"},"reference-count":53,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,4,7]],"date-time":"2022-04-07T00:00:00Z","timestamp":1649289600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>The effects of L-citrulline or L-arginine supplementation on exercise performance are equivocal, and the effects on swimming performance are unclear. We aimed to assess whether 8-day supplementation with L-arginine or L-citrulline supplementation would improve 200 m and 100 m freestyle swimming time-trial performances. After the baseline trial (first visit), in a double-blind, randomised design, 15 trained\/developmental (5 females) swimmers and triathletes were assigned to three groups and underwent an 8-day supplementation period, with a daily dose of either 8 gr L-arginine (Arg, n = 5) or L-citrulline (Cit, n = 5) or placebo (Pla, n = 5). On day 9, participants completed experimental trial (second visit). In each trial, after blood sampling, participants performed both 200 m and 100 m freestyle swimming time-trials, with 30 min recovery between trials. Plasma nitric oxide (NOx) and blood lactate concentrations (BLa) were collected immediately before and after 200 m and 100 m TTs, respectively. No significant difference was observed in NOx between groups (p = 0.201). There was no significant difference in 200 m (p = 0.226) and 100 m swimming time-trials (p = 0.993) between groups. There was a main effect of time on BLa concentration (p &lt; 0.001), but no trial \u00d7 group (p = 0.243) and trial \u00d7 lactate \u00d7 group interaction effect (p = 0.276) was present. Furthermore, 8-day either L-citrulline or L-arginine supplementation did not enhance middle (200 m) and short-distance (100 m) swimming performance in trained\/developmental swimmers and triathletes. These findings do not support the use of L-citrulline or L-arginine supplementation as ergogenic aids for swimming performance.<\/jats:p>","DOI":"10.3390\/ijerph19084462","type":"journal-article","created":{"date-parts":[[2022,4,7]],"date-time":"2022-04-07T13:39:51Z","timestamp":1649338791000},"page":"4462","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Eight Days of L-Citrulline or L-Arginine Supplementation Did Not Improve 200-m and 100-m Swimming Time Trials"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3559-2854","authenticated-orcid":false,"given":"Ozcan","family":"Esen","sequence":"first","affiliation":[{"name":"Department of Health Professions, Manchester Metropolitan University, Manchester M15 6GX, UK"},{"name":"Institute of Sport, Manchester Metropolitan University, Manchester M155TN, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1771-861X","authenticated-orcid":false,"given":"Mustafa Can","family":"Eser","sequence":"additional","affiliation":[{"name":"Faculty of Sport Sciences, Ankara University, G\u00f6lba\u015f\u0131, Ankara 06830, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mekki","family":"Abdioglu","sequence":"additional","affiliation":[{"name":"Faculty of Sport Sciences, Ankara University, G\u00f6lba\u015f\u0131, Ankara 06830, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniela","family":"Benesova","sequence":"additional","affiliation":[{"name":"Sport Centrum Faculty of Pedagogy, University of West Bohemia, 30100 Pilsen, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomasz","family":"Gabrys","sequence":"additional","affiliation":[{"name":"Sport Centrum Faculty of Pedagogy, University of West Bohemia, 30100 Pilsen, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9058-1918","authenticated-orcid":false,"given":"Raci","family":"Karayigit","sequence":"additional","affiliation":[{"name":"Faculty of Sport Sciences, Ankara University, G\u00f6lba\u015f\u0131, Ankara 06830, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1152\/physrev.2001.81.1.209","article-title":"Physiology of nitric oxide in skeletal muscle","volume":"81","author":"Stamler","year":"2001","journal-title":"Physiol. 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