To investigate the medium-term benefits of a swimming program in schoolchildren and adolescents with moderate persistent atopic asthma (MPAA). A randomized, prospective study of children and adolescents (age 7-18 years) with MPAA was carried out at the Hospital de Clínicas of Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil. After a 1-month run-in period, 61 patients (34 female) were randomized into two groups, a swimming group (n = 30) and a control group (n = 31), and followed for 3 months. Both patient groups received inhaled fluticasone (dry powder, 250 mcg twice a day) and salbutamol as needed. The swim training program consisted of two weekly classes over a 3-month period for a total of 24 sessions. Both groups underwent spirometric assessment and methacholine challenge test--provocative concentration of methacholine causing a 20% fall in FEV1 (PC₂₀)--before and after the study period. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured only in the swimming group. Significant increases in PC₂₀ (pre-training, 0.31±0.25; post-training, 0.63±0.78; p = 0.008), MIP (pre-training, 67.08±17.13 cm H₂O; post-training 79.46±18.66; p < 0.001), and MEP (pre-training, 71.69±20.01 cm H₂O; post-training, 78.92±21.45 cm H₂O; p < 0.001) were found in the swimming group. Children and adolescents with MPAA subjected to a swim training program experienced a significant decrease in bronchial hyperresponsiveness, as determined by increased PC₂₀ values, when compared with asthmatic controls who did not undergo swim training. Participants in the swimming group also showed improvement in elastic recoil of the chest wall.86384-90