title: High prevalence of asthma in cross country skiers.
abstract: OBJECTIVE
  To study the prevalence of asthma (asthma symptoms and bronchial hyperresponsiveness) in Swedish cross country skiers compared with non-skiers and monitor changes in symptoms and bronchial hyperresponsiveness during the year.
  
  
  METHODS
  Cross sectional study during the winter ski season and in the summer.
  
  
  METHODS
  Six ski clubs for élite skiers (total 47) in two different areas of Sweden.
  
  
  METHODS
  42 élite cross country skiers and 29 non-skiing referents.
  
  
  METHODS
  Bronchial responsiveness, asthma symptoms, and lung function.
  
  
  RESULTS
  Bronchial responsiveness was significantly greater and asthma symptoms more prevalent in the skiers than in the referents. There was no difference in bronchial responsiveness within either group between winter and summer. 15 of the 42 skiers used antiasthmatic drugs regularly and 23 had a combination of asthma symptoms and hyperresponsive airways or physician diagnosed asthma, or both. Altogether 33 skiers had symptoms of asthma or bronchial hyperresponsiveness. One of the referents had symptoms of asthma and bronchial hyperresponsiveness, and none used antiasthmatic drugs regularly.
  
  
  CONCLUSIONS
  Asthma, asthma-like symptoms, and bronchial hyperresponsiveness are much more common in cross country skiers than in the general population and non-skiers. Strenuous exercise at low temperatures entailing breathing large volumes of cold air is the most probable explanation of persistent asthma in skiers.
authors.affiliation: Respiratory Division, IFL, National Institute of Occupational Health, Solna, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Larsson
authors.forename: P
authors.initials: P
authors.lastname: Ohlsén
authors.forename: L
authors.initials: L
authors.lastname: Larsson
authors.forename: P
authors.initials: P
authors.lastname: Malmberg
authors.forename: P O
authors.initials: PO
authors.lastname: Rydström
authors.forename: H
authors.initials: H
authors.lastname: Ulriksen
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012621:Seasons; D012865:Skiing / Q000502:physiology*; D013548:Sweden / Q000453:epidemiology