Training Schedule and Sleep in Adolescent Swimmers

• Published in: Pediatric Exercise Science
• Main Author: Gudmundsdottir, Sigridur Lara
• Other Authors: Rannsóknarstofa í íþrótta- og heilsufræði (HÍ), Research Centre for Sport and Health Sciences (UI), Menntavísindasvið (HÍ), School of Education (UI), Háskóli Íslands, University of Iceland
• Format: Article in Journal/Newspaper
• Language: English
• Published: Human Kinetics 2020
• Subjects: Early morning training; Intraindividual variability; Swimming; Íþróttafólk; Afreksíþróttir; Sundíþróttir; Svefn; Svefnvenjur; Svefnleysi; Iceland
• Online Access: https://hdl.handle.net/20.500.11815/2351; https://doi.org/10.1123/pes.2019-0067

Publisher's version (útgefin grein) Insufficient sleep duration may affect athletic performance and health. Inconsistent sleep pattern also has negative health effects, but studies on athletes’ intraindividual sleep variability are scarce. The aim of this research was to compare total sleep time (TST) and variability (TST-variability), wakening after sleep onset, and sleep efficiency, during nights preceding early morning practices with other nights, and to investigate sleep characteristics of nights following a day with early morning only, evening only, or both a morning and an evening session in adolescent swimmers. Methods: Wrist-worn accelerometers were used to measure 1 week of sleep in 108 swimmers (mean age 16.1 [2.6] y) in Iceland. Adjusted regression analyses and linear mixed models were used to explore associations of training schedules with TST, TST-variability, wakening after sleep onset, and sleep efficiency. Results: Mean TST was 6:32 (h:min) (±39 min) and TST-variability was 63 minutes (±25 min). TST decreased and TST-variability increased with more early morning practices. TST preceding early training was 5:36 and 5:06 in <16- and ≥16-year-olds, respectively, shorter than on nights preceding later or no morning training (P < .001). Conclusion: Swimmers have extremely short TST preceding early morning sessions and increased TST-variability with more early morning sessions. The Icelandic Sport Fund funded this study. The Icelandic Sport Fund had no role in the design, analysis, or writing of this article. The author certifies that she has no affiliations with or involvement in any organization or entity with any financial interest, or nonfinancial interest in the subject matter or materials discussed in this manuscript. S.L.G. received funding, designed and executed the study, performed the statistical analyses, and wrote the manuscript. Peer Reviewed