{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T18:54:29Z","timestamp":1767034469764,"version":"3.48.0"},"reference-count":40,"publisher":"Public Library of Science (PLoS)","issue":"12","license":[{"start":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T00:00:00Z","timestamp":1766966400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Faculty of Sport Science, Burapha University, Thailand."}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\n Objectives<\/jats:title>\n To identify the key variables influencing 50 m sprint performance in front crawl and butterfly strokes and determine the predominant predictors of sex-related performance differences in each technique in age-group swimmers.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n Thirty national-level age-group swimmers (15 boys and 15 girls; age 13.5\u2009\u00b1\u20091.0 years) underwent assessments of anthropometry, biological maturation, neuromuscular performance (dynamic strength index of upper and lower limbs), anaerobic critical velocity, tethered swimming force, and stroke mechanics.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Multivariate analyses revealed substantial sex differences (p\u2009<\u20090.05), with boys outperforming girls in upper-body force output and anaerobic critical velocity (AnCV). Boys showed a greater AnCV (1.54 vs. 1.45 m\u00b7s\u2009\u207b\u2009\u00b9) and lower fatigue index (\u22128.52% in front crawl). Boys and girls had a 27.60 N front crawl force differential and 13.59 N butterfly force difference in the first 10 s of tethered swimming. Controlling for sex and biological maturity, the maximum explained variation (\u019e\n 2<\/jats:sup>\n ) was found in front crawl tethered swimming force (47%), and butterfly lower limb neuromuscular performance (29%). In front crawl, total push-up peak force (diff: 215.44 N; 95% CI: 1.25 to 3.08; p\u2009<\u20090.001) and body height (diff: 0.08 cm; 95% CI: \u22121.82 to \u22120.28; p\u2009<\u20090.001) were key discriminators, while in butterfly, push-up force (diff: 215.44 N; 95% CI: 1.25 to 3.08; p\u2009<\u20090.001) and stroke index (diff: 0.54 m\u00b2\u2009\u22c5\u2009s\u2009\u207b\u2009\u00b9; 95% CI: 1.04 to 2.79; p\u2009<\u20090.001) were the most effective predictors.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n Our findings confirm the predictive ability of upper-limb neuromuscular performance and stroke efficiency in identifying sex-based differences in sprint swimming. The practical implications of these findings are substantial, offering a framework for coaches and sports scientists to improve procedures for training by focusing on technique- and sex-specific performance characteristics at critical stages of athletic development.<\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0339480","type":"journal-article","created":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T18:42:26Z","timestamp":1767033746000},"page":"e0339480","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Sex-based differences in front crawl and butterfly sprint performance in age-group swimmers"],"prefix":"10.1371","volume":"20","author":[{"given":"Radomyos","family":"Matjiur","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2605-4181","authenticated-orcid":true,"given":"Phornpot","family":"Chainok","sequence":"additional","affiliation":[]},{"given":"Jessy","family":"Lauer","sequence":"additional","affiliation":[]},{"given":"Weerawat","family":"Limroongreungrat","sequence":"additional","affiliation":[]},{"given":"Karla","family":"de Jesus","sequence":"additional","affiliation":[]},{"given":"Rodrigo","family":"Zacca","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5811-0443","authenticated-orcid":true,"given":"Ricardo J.","family":"Fernandes","sequence":"additional","affiliation":[]},{"given":"J. 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