Intense training: mucosal immunity and incidence of respiratory infections

• Published in: European journal of applied physiology Vol. 93; no. 4; pp. 421 - 428
• Main Authors: Tiollier, E, Gomez-Merino, D, Burnat, P, Jouanin, J-C, Bourrilhon, C, Filaire, E, Guezennec, C Y, Chennaoui, M
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01-01-2005
• Subjects: Adaptation, Physiological - immunology; Adult; Exercise; Exercise Tolerance - immunology; France - epidemiology; Humans; Immunoglobulin A - immunology; Incidence; Male; Medical research; Military Personnel - statistics & numerical data; Mouth Mucosa - immunology; Physical Exertion; Respiratory Tract Infections - epidemiology; Respiratory Tract Infections - immunology; Saliva - immunology; Stress, Physiological - immunology; France
• ISSN: 1439-6319; 1439-6327
• DOI: 10.1007/s00421-004-1231-1

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.