Physical activity among people with an inflammatory bowel disease: a systematic review of antecedents.

People with an inflammatory bowel disease experience challenges that can severely limit their quality of life. Physical activity intervention may be an efficacious method to improve outcomes of inflammatory bowel disease, however many people with an inflammatory bowel disease do not meet physical activity guidelines. The current review aims to synthesize available literature on the factors influencing physical activity in inflammatory bowel disease and identify differences between two main subgroups: Crohn's disease and ulcerative colitis. Six databases were searched for all studies published until 31 August 2023, which collected data regarding physical activity antecedents within a population of persons with an inflammatory bowel disease. The identified antecedents were contextualized within the COM-B model for behaviour change to provide implications for physical activity interventions. The search resulted in 1816 titles and abstracts, of which 30 full-text papers were screened and 14 papers met inclusion criteria for this review. A modified thematic analysis integrating quantitative and qualitative data among 3,985 participants identified disease activity, fatigue, depression, pain and urgency as the most influential antecedents to physical activity. These antecedents were identified as factors affecting physical capability, reflective motivation and physical opportunity within the COM-B model. Persons with Crohn's disease were found to be more susceptible to barriers and engage in less total physical activity than those with ulcerative colitis, however such a small number of studies weakens this finding. Future research should emphasize the collection of longitudinal and experimental data among antecedents of physical activity in a homogenous sample, such that definitive quantitative syntheses can be conducted.