Introduction: Regular exercise and physical activity participation are recommended in guideline-based care for individuals with cystic fibrosis (CF) across the spectrum of age and disease severity. However, the best training methods to improve physical function and encourage ongoing exercise and activity participation are not clear, which is an ongoing challenge for clinicians. Areas covered: This perspective provides an overview of current evidence for exercise and physical activity relative to clinical outcomes and health-care utilization in people with CF, and highlights areas of future research need. Expert commentary: What kind, how much, how often, and how best to support people with CF to be physically active is uncertain. Whether new methods of training, the use of technology, or pharmaceutical developments could best deliver increased activity and physiological benefit without increased therapeutic burden is unclear. At present, if people with CF are going to be physically active, seemingly they should aim to perform this activity in the way most likely to confer some health benefit i.e. concerted exercise bouts of at least 10 min in addition to any incidental (habitual) activity performed during the course of daily life.