title: Mucosal immunity and upper respiratory tract symptoms in recreational endurance runners.
abstract: The present study investigated the effects of a 12-week endurance-training intervention on salivary proteins and upper respiratory tract symptoms (URS) in 25 young men. Saliva samples of 25 recreational male endurance runners (age 34.6 years, body mass index = 23.8 kg·m(-2), peak aerobic capacity = 47.2 mL·kg(-1)·min(-1)) were collected before (PRE) and after (POST) the training intervention, in a fasting state, as well as both before and after a maximal incremental treadmill run. The training consisted of both continuous and interval training sessions, 4-6 times per week based on the polarized training approach. Participants filled in Wisconsin Upper Respiratory Symptom Survey-21 and were retrospectively divided into 2 groups according to whether they reported URS (URS group, n = 13) or not (HEALTHY group, n = 12). Basal salivary immunoglobulin A (sa-sIgA) levels were significantly higher (+70%, p < 0.05) in the HEALTHY group both at PRE and POST whereas no significant differences were observed in salivary immunoglobulin M, salivary immunoglobulin G, lysozyme, or salivary α-amylase activity (sAA). Sa-sIgA concentration at PRE significantly correlated with the number of sick-days (R = -0.755, p < 0.001) in all subjects. The incremental treadmill run acutely increased sAA significantly (p < 0.05) at PRE (200%) and POST (166%) in the HEALTHY group but not in the URS group. This study demonstrated that subjects, who experienced URS during the 12 weeks of progressive endurance training intervention, had significantly lower basal sa-sIgA levels both before and after the experimental endurance training period. In addition to sa-sIgA, acute sAA response to exercise might be a possible determinant of susceptibility to URS in endurance runners.
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.|Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.
authors.forename: Johanna K
authors.initials: JK
authors.lastname: Ihalainen
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.|Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.
authors.forename: Moritz
authors.initials: M
authors.lastname: Schumann
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.|Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.
authors.forename: Keijo
authors.initials: K
authors.lastname: Häkkinen
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.|Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.
authors.forename: Antti A
authors.initials: AA
authors.lastname: Mero
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D015992:Body Mass Index; D001835:Body Weight; D060467:Disease Resistance / Q000276:immunology*; D006801:Humans; D018928:Immunity, Mucosal; D007070:Immunoglobulin A / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D008297:Male; D010807:Physical Endurance / Q000276:immunology*; D012137:Respiratory System / Q000276:immunology*; D012140:Respiratory Tract Diseases / Q000453:epidemiology*; D012189:Retrospective Studies; D012420:Running / Q000502:physiology*; D012463:Saliva / Q000737:chemistry / Q000276:immunology; D055291:Salivary alpha-Amylases / Q000378:metabolism; D011795:Surveys and Questionnaires; D014922:Wisconsin
chemical_list: D015415:Biomarkers; D007070:Immunoglobulin A; D007075:Immunoglobulin M; D055291:Salivary alpha-Amylases
keywords: antimicrobial proteins; endurance training; entraînement en endurance; exercise immunology; health; immunologie de l’exercice; performance; protéines antimicrobiennes; saliva; salive; santé; symptômes des voies respiratoires supérieures; upper respiratory tract symptoms