A single bout of maximal exercise improves lung function in patients with cystic fibrosis.

BACKGROUND: Responses to a single bout of exercise may provide critical information for maximizing improvements in pulmonary function following exercise training in cystic fibrosis (CF). We sought to determine if acute maximal exercise improves pulmonary function in patients with CF.

METHODS: Thirty-three patients with CF completed a comprehensive assessment of pulmonary function to determine forced vital capacity (FVC), forced expiratory volume in one second (FEV1 ), and lung clearance index (LCI) prior to and immediately following maximal aerobic exercise on a cycle ergometer.

RESULTS: Following exercise, FVC (∆0.08±0.14L) and FEV1 (∆0.06±0.15L) increased, while LCI decreased (∆-0.71±0.93) (all p<0.05). Changes in FEV1 (%predicted) were associated with peak work (r=0.40, p=0.02) and peak pulmonary ventilation (r=0.45, p=0.01).

CONCLUSIONS: A single bout of maximal exercise acutely improves pulmonary function in patients with CF and improvements may be related to peak work and peak pulmonary ventilation.