The impact of sleeping with reduced glycogen stores on immunity and sleep in triathletes.

Autor:	Louis, Julien, Marquet, Laurie-Anne, Tiollier, Eve, Bermon, Stéphane, Hausswirth, Christophe, Brisswalter, Jeanick, Bermon, Stéphane
Předmět:	SLEEP HEALTH TRIATHLETES NUTRITIONAL requirements GLYCOGEN ENDURANCE riding (Equestrianism) CARBOHYDRATE metabolism COMPARATIVE studies CARBOHYDRATE content of food IMMUNITY IMMUNOLOGICAL adjuvants LOW-carbohydrate diet RESEARCH methodology MEDICAL cooperation ORAL drug administration PHYSICAL fitness RESEARCH RESPIRATORY infections SPORTS EVALUATION research RANDOMIZED controlled trials PREVENTION
Zdroj:	European Journal of Applied Physiology; Oct2016, Vol. 116 Issue 10, p1941-1954, 14p, 2 Diagrams, 4 Charts, 5 Graphs
Abstrakt:	Purpose: We investigated the effects of a 3-week dietary periodization on immunity and sleep in triathletes.Methods: 21 triathletes were divided into two groups with different nutritional guidelines during a 3-week endurance training program including nine twice a day sessions with lowered (SL group) or maintained (CON group) glycogen availability during the overnight recovery period. In addition to performance tests, sleep was monitored every night. Systemic and mucosal immune parameters as well as the incidence of URTI were monitored every week of the training/nutrition protocol. Two-ways ANOVA and effect sizes were used to examine differences in dependent variables between groups at each time point.Results: The SL group significantly improved 10 km running performance (-1 min 13 s, P < 0.01, d = 0.38), whereas no improvement was recorded in the CON group (-2 s, NS). No significant changes in white blood cells counts, plasma cortisol and IL-6 were recorded over the protocol in both groups. The vitamin D status decreased in similar proportions between groups, whereas salivary IgA decreased in the SL group only (P < 0.05, d = 0.23). The incidence of URTI was not altered in both groups. All participants in both groups went to bed earlier during the training program (SL -20 min, CON -27 min, P < 0.05, d = 0.28). In the SL group, only sleep efficiency slightly decreased by 1.1 % (P < 0.05, d = 0.25) and the fragmentation index tended to increase at the end of the protocol (P = 0.06).Conclusion: Sleeping and training the next morning regularly with reduced glycogen availability has minimal effects on selected markers of immunity, the incidence of URTI and sleeping patterns in trained athletes. [ABSTRACT FROM AUTHOR]
Databáze:	Complementary Index
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