IMPROVEMENTS IN PHYSICAL ACTIVITY AND PHYSIOLOGICAL ADAPTATION IN ADULTS WITH CYSTIC FIBROSIS

To undertake this research, a multi-methods approach was used to explore physical activity (PA) in adults with Cystic Fibrosis (CF). Study 1 was a systematic review of the literature and reported that adults with CF were insufficiently active to achieve PA recommendations, but their PA levels were largely comparable to their non-CF peers. The tools used to assess PA and outcomes reported in the literature were variable, many of which did not provide sufficient information to assess relevant components of PA, highlighting a requirement for high quality studies designed specifically to explore PA in adults with CF. Study 2 included objective assessments of PA in 62 participants (31 with CF and 31 controls) using ActiGraph accelerometers. Quality of life (QoL) and self-reported PA were assessed using questionnaires. Vascular function (a marker of CVD risk) was assessed using flow-mediated dilatation (FMD) in sub-groups of adults with CF (n=12) and matched controls (n=12). Participants with CF engaged in significantly less moderate-to-vigorous PA (MVPA) than their non-CF peers, with significantly steeper intensity gradients, demonstrating a daily profile of PA with more time spent engaging in lower intensity PA and less time spent engaging in higher intensity PA. Higher levels of vigorous PA were positively correlated with lung function and QoL. There was no significant difference in FMD between groups or any association with objectively assessed PA. Study 3 involved semi-structured interviews to explore patients’ (n=11) perceptions of PA, devised using the PRECEDE component of the PRECEDE-PROCEED model. Phase 2 included focus groups to discuss the perceived barriers, facilitators and opportunities for PA participation and how this information could inform the promotion of PA in adults with CF. Separate focus groups were conducted with individuals with CF (n=9) and their families and CF clinicians (n=3). The principle predisposing barriers identified related to participants physical and mental wellbeing, which manifested as both a barrier and a facilitator of PA behaviour. Participants perceived that PA had the potential to slow the rate of clinical deterioration and manage the symptoms associated with the condition. Despite recognition of the potential benefits of PA, it appears that enjoyment is an important correlate of PA. The presence of health care professionals with a special interest in PA within CF MDTs and clinics was reported as a key reinforcing factor for PA behaviour. The family were also reported as reinforcing factors for PA behaviour. Finally, the transition process, during adolescence and early adulthood was reported as an important period in the life of an individual with CF, with both participants with CF and their clinicians suggesting that PA should be promoted as early as possible. The promotion of PA in adults with CF may not be best achieved through the delivery of a single intervention but through the role of an exercise professional as part of long-term routine CF care. PA promotion should begin during paediatric care and be reinforced throughout an individual’s life with additional support during adolescence. The role of an exercise professional should be to identify the principle predisposing, enabling, reinforcing factors influencing PA behaviour at an individual level in order to remove barriers to PA, engage patients and improve ‘wellbeing’. This thesis contributes evidence to inform the use of accelerometry, including the use of raw data analysis and metrics such as average Euclidean Norm Minus One (ENMO) and the intensity gradient, which provide a comprehensive PA profile that may allow tailored PA advice for adults with CF, without requiring CF-specific PA cut-points. Additionally, this thesis provides an insight into the correlates of PA in this population, which may help to inform future PA activity promotion interventions. Future research should employ robust PA assessment methods and explore the role of exercise professional led PA promotion as part of routine CF care