Swimmers show the highest prevalence of asthma among elite athletes, certainly due to chlorine exposure. The consequences of a chronic exposure to chlorine compounds by swimmers and the mechanisms of asthme in this population are still poorly documented. Specific diagnostic criteria have been proposed by the International Olympic Committee - Medical Council (IOC-MC) and World anti-doping agency (WADA) to determine the presence of asthma in athletes. Using the more specific bronchial provocation tests, our aims are

1. to compare the prevalence of asthma in swimmers and control subjects
2. to analyze the Influence of chlorine exposure on bronchial inflammatory processes in swimmers versus control subjects
3. to study the time-course of changes in airway symptoms, responsiveness, inflammation and remodeling after cessation of training

Inclusion Criteria:

• 14 to 35 years old
• To swim at least 10h per week
• For control subjects, non-competitive healthy subjects

Exclusion Criteria:

• any disease that may interfere with the tests for the controls
• Triathletes are excluded
• Smokers
• Obese or with a BMI more than 29
• Former athletes (control group)

Swimmers from Quebec swimming school and universities Control from université Laval or secondary School