Can physical exercise help people with irritable bowel syndrome? How substantial is the evidence?

Purpose: Irritable bowel syndrome is one of the most common gastrointestinal disorders worldwide that negatively affect health and quality of life and imposes high costs. Increasing attention is being paid to non-pharmacological therapies, like physical exercise, to manage and alleviate irritable bowel syndrome symptoms, but the underlying mechanism is unclear, and the evidence is inconclusive. This article aims to provide an overview analysis of the recent evidence that links physical exercise with irritable bowel symptoms. Material and methods. For the last five years of research (2018-2023), we searched several international scientific databases, including Web of Science, Scopus, Science Direct, ADI, the Cochrane Central Register of Controlled Trials, PubMed, Medline, Clinical trials.gov, Google Scholar, and the WHO database. Results. Generally, exercise exerts variable effects on gut physiology, integrity, and health. Much research recommended adopting regular light-to-moderate aerobic exercise and relaxation anaerobic exercise to enhance the patient’s psychological well-being and alleviate global irritable bowel syndrome symptoms. These types of exercise are purported to improve bowel function, motility, tone, habits, immunity, microbial diversity, and quality of life due to a decrease in psychological stress, depression, anxiety index, irritable bowel syndrome symptom severity score, intestinal hypersensitivity, and gut permeability. In contrast, more studies reported several disruptive effects of vigorous aerobic exercise on gut integrity and physiology that can compromise irritable bowel syndrome symptoms by inducing splanchnic hypoperfusion, gastrointestinal epithelial wall damage, malabsorption, dysbiosis, and bacterial translocation, thus calling into question the positive outcomes of the exercise. Conclusions. There is overwhelming evidence recommending regular light-to-moderate aerobic exercise and anaerobic relaxation exercises for patients with IBS. However, this evidence seems low-quality, making it challenging to confirm the actual impacts of exercise. Ethnicity, study design, type and intensity of exercise, and methodological issues are among the reasons that are put forward to account for this low-quality evidence. Thus, well-designed plausible studies, particularly randomized controlled trials and research on individualized exercise intervention settings that consider exercise frequency, intensity, time, type, volume, and progression, are highly demanded to enable drawing specific exercise recommendations for irritable bowel syndrome patients without adverse effects.