Mucosal immunity and illness incidence in elite rugby union players across a season

Brian Cunniffe, Hywel Griffiths, Wayne Proctor, Bruce Davies, Julien S. Baker, Ken P. Jones

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

PurposeTo examine the relationship between upper respiratory illness (URI) incidence with changes in mucosal immunity (saliva immunoglobulin A (s-IgA) and saliva lysozyme (s-Lys)) and training load (TL) in a squad of elite rugby union players. 
MethodsTimed resting morning saliva samples were taken from players (n = 31) at preselected time points for 11 months. Weekly illness rates and TL were assessed using a Web-based diary and from medical/coaching staff reports. 
ResultsNo significant correlation was found between absolute s-IgA or s-Lys concentrations and URI incidence. Peaks in URI (December and March) were preceded by periods of increased training intensity and reduced game activity. In 23% of all URI episodes, players reported that presence of an illness either reduced activity (14.4%) or felt the need to go to bed (8.6%). When s-IgA concentration was expressed relative to that when in a URI-free state, a 15% reduction (P = 0.08) was observed in individuals who had present URI symptoms. Decreases in absolute s-IgA (December) and s-Lys (November and February) concentrations were associated with a corresponding increase in saliva cortisol (P < 0.05). Lower s-IgA (P < 0.05) and s-Lys concentrations were consistently observed in backs than forwards, whereas URI incidence also differed for player position (3.4 forwards vs 4.3 backs). 
ConclusionsRegular monitoring of s-IgA and s-Lys may be useful in the assessment of exercise stress and URI risk status in elite team sport athletes. A combination of alterations in training intensity and seasonal influence is a likely contributor to observed peaks in URI incidence. It is probable that stress-induced increases in cortisol release contribute to reductions in mucosal immunity, which, when lowered, predispose rugby players to increased risk of illness.
Original languageEnglish
Pages (from-to)388-397
Number of pages10
JournalMedicine & Science in Sports & Exercise
Volume43
Issue number3
DOIs
Publication statusPublished - Mar 2011

Keywords

  • INFECTION
  • MONITORING
  • ATHLETES
  • IMMUNE FUNCTION

Cite this

Cunniffe, B., Griffiths, H., Proctor, W., Davies, B., Baker, J. S., & Jones, K. P. (2011). Mucosal immunity and illness incidence in elite rugby union players across a season. Medicine & Science in Sports & Exercise, 43(3), 388-397. https://doi.org/10.1249/MSS.0b013e3181ef9d6b