Feasibility Assessment of Cardiovascular Endurance Training for the Symptomatic Improvement of Irritable Bowel Syndrome Patients With a Sedentary and Non-active Lifestyle.

Inclusion Criteria: * Patients aged 18 - 60 years; * Fulfilling the ROME IV criteria for Irritable bowel syndrome (IBS); * Moderate symptom severity as defined by a IBS-Symptom Severity Scale \> 175; * Sedentary lifestyle defined as SIT-Q-7D \> 8h/day; * Physically inactive defined as \< 150min/week on the IPAQ score Exclusion Criteria: * Cardiorespiratory disorder hampering participation in a program of physical exercise as evidenced by the sport + keuringsartsen (SKA) questionnaire. * Clinical suspicion of an organic disorder different from IBS (patients can be included when this disorder had been excluded); * Known inflammatory bowel disorder; * Known intestinal motility disorder; * Alcohol (defined as more than 14 U per week) or other substance abuse; * Active psychiatric disorder; * Known systemic or auto-immune disorder with implication for the GI system; * Prior abdominal surgery (with the exception of appendectomy or cholecystectomy more than 6 months ago); * Any prior diagnosis of cancer other than basocellular carcinoma; * Current chemotherapy; * History of gastro-enteritis in the past 8 weeks; * Change in diet in the past 8 weeks; * Dietary supplements unless taken at a stable dose for more than 8 weeks; * Antibiotics, pre-, pro-, post-biotics or any combination during the past 8 weeks; * Treatment with neuromodulators (one neuromodulator taken at a stable dose for more than 12 weeks is allowed); * Treatment with spasmolytic agents, opioids, loperamide, gelatine tannate or mucoprotect-ants during the past 8 weeks.