Physical activity is widely recommended in the treatment and management of cystic fibrosis (CF). Despite the numerous physical and psychological benefits, many young people with CF are not achieving the recommended levels of physical activity. The aim of this systematic review was to identify and synthesise available qualitative investigations exploring the motives for, barriers to and facilitators of physical activity among young people with CF.
The following six electronic databases were systematically searched: Applied Social Sciences Index and Abstracts (ASSIA), CINAH, EMBASE, MEDLINE, MEDLINE-in-process, PsycINFO up to August 2019. Keywords were used to identify qualitative research that explored engagement in physical activity among young people with CF. Titles and abstracts were screened by two independent reviewers, and potentially relevant articles were retrieved in full. Articles were eligible for inclusion if they employed any qualitative method and recruited participants under the age of 24 years with CF. Risk of bias of included studies was assessed via the Critical Appraisal Skills Programme. Results were synthesised using a thematic approach.
Seven studies met our inclusion criteria and were included in the review. Overall, studies were of moderate to high quality. Thematic synthesis identified nine main themes that encompass motives for, barriers to and facilitators of physical activity among young people with CF. These were (1) Perceptions of physical activity. (2) Value attributed to physical activity. (3) Social influences. (4) Competing priorities. (5) Fluctuating health. (6) Normality. (7) Control beliefs. (8) Coping strategies. (9) Availability of facilities. Previous reviews have been unable to identify intervention characteristics that influence physical activity behaviour.
This review provides detailed information on the physical (biological-clinical), psychological, social and environmental influences on physical activity behaviour, thus providing numerous targets for future interventions. This in turn could facilitate promotion of physical activity among young people with CF.

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