Intense training: mucosal immunity and incidence of respiratory infections

Eur J Appl Physiol. 2005 Jan;93(4):421-8. doi: 10.1007/s00421-004-1231-1. Epub 2004 Oct 14.


This investigation examined the impact of a multistressor situation on salivary immunoglobulin A (sIgA) levels, and incidence of upper respiratory tract infection (URTI) during the French commando training (3 weeks of training followed by a 5-day combat course). For the URTI, the types of symptoms were classified according to the anatomical location of the infection. Saliva samples were collected (8 a.m.) from 21 males [21 (2) years] before entry into the commando training, the morning following the 3 weeks of training, after the 5-day combat course, and after 1 week of recovery. sIgA, protein and cortisol concentrations were measured. Symptoms of URTI were recorded during the study from health logs and medical examinations. After the 3 weeks of training, the sIgA concentration was not changed, although it was reduced after the 5-day course [from 120 (14) mg l(-1) to 71 (9) mg l(-1), P<0.01]. It returned to pre-training levels within a week of recovery. The incidence of URTI increased during the trial (chi(2)=53.48; P<0.01), but was not related to sIgA. Among the 30 episodes of URTI reported, there were 12 rhino-pharyngitis, 6 bronchitis, 5 tonsillitis, 4 sinusitis and 3 otitis. Cortisol levels were raised after the 3-week training (P<0.01), dropping below baseline after the combat course (P<0.01). Stressful situations have an adverse effect on mucosal immunity and incidence of URTI. However, the relationship between sIgA and illness remained unclear. The large proportion of rhino-pharyngitis indicated that the nasopharyngeal cavity is at a higher risk of infection.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / immunology
  • Adult
  • Exercise
  • Exercise Tolerance / immunology*
  • France / epidemiology
  • Humans
  • Immunoglobulin A / immunology*
  • Incidence
  • Male
  • Military Personnel / statistics & numerical data*
  • Mouth Mucosa / immunology*
  • Physical Exertion
  • Respiratory Tract Infections / epidemiology*
  • Respiratory Tract Infections / immunology*
  • Saliva / immunology*
  • Stress, Physiological / immunology*


  • Immunoglobulin A