| Circadian effects on the acute responses of salivary cortisol and IgA in well trained swimmers. | |
| | |
MedLine Citation:
|
PMID: 12145115 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
OBJECTIVE: To examine whether time of day significantly affects salivary cortisol and IgA levels before and after submaximal swimming. METHODS: Fourteen male competitive swimmers (mean (SD) age 18 (3.2) years) volunteered to participate in the study. In a fully randomised, cross over design, each subject performed 5 x 400 m front crawl at 85 (1.2)% of their seasonal best time (277 (16) seconds), with one minute rest between each 400 m, at 0600 and 1800 hours on two separate days. Timed, unstimulated saliva samples were collected before and after exercise. Saliva samples were analysed for cortisol and IgA by radioimmunoassay and single radial immunodiffusion respectively. RESULTS: Significant time of day effects (am and pm respectively) were observed in IgA concentration (0.396 (0.179) v 0.322 (0.105) mg/ml, p<0.05), IgA secretory rate (0.109 (0.081) v 0.144 (0.083) mg/min, p<0.01), and saliva flow rate (0.31 (0.23) v 0.46 (0.22) ml/min, p<0.001) before exercise (all values mean (SD)). Differences in cortisol levels before exercise (1.09 (0.56) v 0.67 (0.94) microg/dl) approached significance (p = 0.059). The exercise protocol did not significantly affect IgA concentration and secretory rate (p>0.05) but, in comparison with values before exercise, caused significant alterations in cortisol (p<0.01) and saliva flow rate (p<0.01). There was no significant interaction effect of time of day by exercise on any salivary variables measured (p>0.05). However, most of the values of the salivary variables before exercise were significantly inversely related to their exercise induced response (p<0.05). CONCLUSION: These results suggest a significant circadian variation in the variables measured before exercise, without showing a significant effect on their acute responses to exercise. |
| | |
Authors:
|
L Dimitriou; N C C Sharp; M Doherty |
Related Documents
:
|
18308895 - The effect of exercise on motor performance tasks used in the neurological assessment o... 17119515 - Seasonal variation of aerobic performance in soccer players according to positional role. 20300035 - Short-term effects of complex and contrast training in soccer players' vertical jump, s... 23686775 - Moderate-intensity single exercise session does not induce renal damage. 10428265 - Reduced oxidative stress during acellular reperfusion of the rat liver after hypothermi... 8911825 - The relationship between test protocol and the development of exercise-induced hypoxemi... |
Publication Detail:
|
Type: Clinical Trial; Journal Article; Randomized Controlled Trial |
Journal Detail:
|
Title: British journal of sports medicine Volume: 36 ISSN: 0306-3674 ISO Abbreviation: Br J Sports Med Publication Date: 2002 Aug |
Date Detail:
|
Created Date: 2002-07-29 Completed Date: 2002-11-08 Revised Date: 2009-11-18 |
Medline Journal Info:
|
Nlm Unique ID: 0432520 Medline TA: Br J Sports Med Country: England |
Other Details:
|
Languages: eng Pagination: 260-4 Citation Subset: IM |
Affiliation:
|
Department of Sport Sciences, Brunel University, Osterley Campus, Borough Road Isleworth, Middlesex TW7 5DU, UK. Lygeri@hotmail.com |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Adolescent Analysis of Variance Circadian Rhythm* Cross-Over Studies Humans Hydrocortisone / analysis* Immunoglobulin A / analysis* Male Saliva / chemistry* Swimming / physiology* |
| Chemical | |
Reg. No./Substance:
|
0/Immunoglobulin A; 50-23-7/Hydrocortisone |
| Comments/Corrections | |
Comment In:
|
Br J Sports Med. 2003 Apr;37(2):187
[PMID:
12663367
]
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Is there a critical period for bone response to weight-bearing exercise in children and adolescents?...
Next Document: A prospective study of injuries to elite Australian rugby union players.