Exercise and physical activity

Physical activity is advised in IBS for general health and for its effects on bowel function: colonic transit is faster in physically active people, and exercise has established benefits in conditions that often travel with IBS, such as depression and fibromyalgia PMID 30232834 PMID 21206488. The 2021 ACG guideline did not issue a recommendation on exercise, so only the UK bodies are listed above.

The best-known trial randomised 102 Swedish patients to physiotherapist-guided advice to increase their physical activity or to maintain their usual lifestyle; among the 75 who completed the study, IBS symptom severity fell by a median of 51 points in the activity group versus 5 points in controls, and fewer active patients experienced worsening symptoms PMID 21206488. A follow-up of 39 of those patients a median of 5.2 years later found symptom severity still lower than baseline, with improvements in quality of life, fatigue, depression, and anxiety, and self-reported weekly activity up from 3.2 to 5.2 hours PMID 25593485.

A 2019 systematic review of 14 randomised trials (683 patients) covering yoga, walking or aerobic activity, tai chi, mountaineering, and qigong concluded that exercise appears feasible and potentially effective but that the trials carried a strong risk of bias, so no firm conclusion about the true effect could be drawn PMID 30232834. A review focused on yoga (six trials, 273 patients) found reduced bowel symptoms, severity, and anxiety versus conventional treatment, with no adverse events in the two trials that reported safety, but judged the study methods too flawed to support a routine recommendation PMID 27112106.

The yoga review’s findings have since been tested head-to-head against diet. A German single-blind trial randomised 59 patients to 12 weeks of yoga, delivered as two sessions a week, or to a low FODMAP diet taught in three nutritional counselling sessions, with blinded assessors at 12 and 24 weeks. Both groups improved substantially from baseline on the IBS Symptom Severity Scale, and there was no statistically significant difference between them at 12 weeks (difference 31.8 points, confidence interval -11.9 to 75.5) or at 24 weeks; one patient in each arm had a serious adverse event PMID 29076171. With roughly 30 per arm the trial could only have found a large difference, so the result is best read as “both approaches were associated with improvement” rather than proof that yoga matches the diet, and it sits alongside the earlier review’s warning that yoga trials are small and methodologically weak PMID 27112106.

Points clinicians commonly raise: the recommendation is strong on weak evidence because the downside is small and the general health case is well established PMID 33903147; what counts is sustained moderate activity rather than any specific sport; vigorous endurance exercise can itself provoke gut symptoms in some people; and activity is framed as a foundation alongside diet and other treatments, not a stand-alone plan.

Talk to a clinician before starting or stopping anything.