Abstract
Background. Physical exercise improves outcomes for patients with cystic fibrosis (CF). Laboratory-based measures obtained at submaximal exercise during cardiopulmonary exercise testing (CPET) have been shown to closely reflect activities of daily living in healthy subjects. To date, the link between daily physical activity and submaximal exercise data obtained during CPET has never been systematically explored in clinically stable adults with CF. Methods. Sixteen stable CF patients (mean age 33 (8) SD yrs; FEV1 2.62 (0.66) l; FEV1 68 (15) % predicted, BMI 22.1 (2.3)) and 15 age- and sex-matched healthy controls were studied at rest and during symptom-limited incremental CPET. Measurements were taken at the lactic threshold (LT) and at peak exercise. The 6MWT was also performed.Daily PA was assessed using the SenseWear (SW) Pro3 Armband accelerometer. Results. Except for peak values, VO2 profile and the VO2 at LT were comparable between CF and controls. No difference was observed in 6MWD between CF and controls. Compared with controls, CF patients had similar values in daily PA at different intensities with higher duration of PA (p=0.04) and higher average of metabolic equivalents (p=0.04). Conclusions: Submaximal exercise data related to aerobic capacity were comparable between CF patients with mild to moderate lung impairment and healthy controls. Daily PA at home without any different changes in chronic therapy might play an important role in maintaining aerobic fitness in adults with CF. CPET is a valuable tool in assessing aerobic fitness in CF and could be used to detect early changes in PA.
- © 2014 ERS