Cystic fibrosis (CF) is a lethal autosomal recessive disease caused by mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), resulting in a build-up of viscous mucus and multi-organ dysfunction. Advances in treatment have decreased the burden of CF and increased survival age. However, clinicians and researchers must continue to look for areas that contribute to improved quantity and quality of life for individuals with CF. The aim of this thesis was to explore the effects of nutritional status, aerobic capacity, and modulator therapy on clinical outcomes within CF patients. Study 1 demonstrated the minimal effective dose of exercise needed to elicit change in aerobic capacity. Safety and efficacy of this protocol was evidenced with increases in aerobic capacity akin to that seen in the general population. Study 2 observed the longitudinal effect nutritional status had on pulmonary function. Female pulmonary function evidenced an increased sensitivity to change in body mass index when compared to males. Study 3 evaluated the lived experience of CFTR treatment, highlighting despite clinically relevant benefits, benefits do not come in the absence of negative physical and psychological challenges. Study 4 demonstrated increased incidence of overweight/obesity following implementation of CFTR treatment Introduction of CFTR treatment has rapidly changed the outlook of CF care. As landscape of the disease changes there is a need to adapt to new individual needs in what is a familiar disease with a new face. Whilst diet and exercise represented significant cornerstones of care in the past 30 years, as disease burden decreases, there is a need to view diet and exercise as means of enhancing physical and psychological health, rather than tools to manage the symptoms of the disease. Whilst this thesis is unable to quantify the effect of CFTR therapy on health, the future has never looked brighter for CF patients.