The relationship between exercise and gastrointestinal (GI) health is complex and bidirectional. While moderate exercise generally promotes gut health by enhancing motility, reducing inflammation, and supporting microbial balance, intense or prolonged physical activity may exacerbate GI symptoms, particularly in individuals with pre-existing digestive disorders. A deeper understanding of this interplay is essential for optimizing both exercise performance and GI well-being.

To synthesize current evidence on exercise-related GI disorders, exploring the prevalence, mechanisms, risk factors, and management strategies associated with exercise-induced GI symptoms.

Following PRISMA guidelines, comprehensive searches of databases, including PubMed, Scopus, Web of Science, and EMBASE were conducted. Studies were included if they focused on exercise-induced GI disorders, encompassed randomized controlled trials, cohort studies, case-control studies, and cross-sectional designs, and addressed symptoms across various exercise modalities. Data were extracted and analyzed to identify patterns and implications for clinical and athletic practice.

A total of 231 studies met the inclusion criteria, highlighting both the benefits and risks of exercise on GI health. Regular moderate-intensity exercise, including activities such as walking, cycling, and yoga has been associated with improved GI function in conditions like gastroesophageal reflux disease, irritable bowel syndrome, inflammatory bowel disease, and constipation. These benefits are attributed to enhanced intestinal motility, reduced systemic inflammation, and improved gut barrier integrity. Additionally, exercise plays a role in regulating the gut-brain axis, with practices like yoga and Tai Chi demonstrating particular effectiveness in alleviating functional GI disorders. Conversely, high-intensity or prolonged exercise may contribute to symptoms such as nausea, diarrhea, and abdominal pain due to mechanisms like splanchnic hypoperfusion and increased intestinal permeability. Individual factors, including fitness level, dietary habits, hydration status, and underlying GI conditions, significantly influence the body's response to exercise.

Moderate-intensity exercise is a beneficial and well-tolerated intervention for promoting GI health, whereas high-intensity activities require careful monitoring, particularly in individuals with pre-existing GI disorders. Personalized exercise and dietary strategies are essential for balancing the benefits of physical activity with the risk of GI distress. Further research is needed to explore the long-term effects of exercise on gut microbiota composition and overall digestive health.

Background: Irritable bowel syndrome (IBS) and obesity are associated with intestinal barrier alterations that result in low-grade inflammation. Zonulin and intestinal fatty acid-binding protein (I-FABP) assess gut barrier health, while urinary indican concentrations reflect dysbiosis in the small intestine. Physical activity, such as Fitwalking, aids weight management and improves intestinal permeability. This study assesses the impact of a 12-week Fitwalking program on intestinal barrier health in IBS patients categorized by body mass index (BMI). Methods: Fifty-seven mild IBS patients were categorized as obese (OB = 18), overweight (OW = 24), or normal weight (NW = 15) and assigned to a walking group. Participants walked thrice weekly at moderate intensity for 60 min per session, using the specific Fitwalking technique, supervised by staff. Results: No significant changes in biochemical or anthropometric variables were observed. However, Fitwalking improved the Global Physical Capacity Score (GPCS) by 46%, 48%, and 24% in the NW, OW, and OB groups. Post-intervention, serum zonulin levels notably decreased in OB individuals, suggesting reduced inflammation. OW patients unexpectedly showed increased fecal zonulin levels. OB participants experienced decreased urinary indican levels. Zonulin levels positively correlated with BMI and inversely with GPCS. Conclusions: Regular exercise benefits the intestinal barrier, especially in obese IBS patients. Monitoring zonulin and I-FABP may offer insights into gut barrier integrity and GI injury severity. Future studies should explore longer intervention durations, larger populations, and advanced diagnostic tools to validate findings and investigate the mechanisms behind exercise-induced changes in intestinal permeability and gut health markers.

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder characterized by abdominal pain, bloating, diarrhea, and constipation. Recent studies have underscored the significant role of the gut microbiota in the pathogenesis of IBS. Physical exercise, as a non-pharmacological intervention, has been proposed to alleviate IBS symptoms by modulating the gut microbiota. Aerobic exercise, such as running, swimming, and cycling, has been shown to enhance the diversity and abundance of beneficial gut bacteria, including Lactobacillus and Bifidobacterium. These bacteria produce short-chain fatty acids that possess anti-inflammatory properties and support gut barrier integrity. Studies involving IBS patients participating in structured aerobic exercise programs have reported significant improvements in their gut microbiota's composition and diversity, alongside an alleviation of symptoms like abdominal pain and bloating. Additionally, exercise positively influences mental health by reducing stress and improving mood, which can further relieve IBS symptoms via the gut-brain axis. Long-term exercise interventions provide sustained benefits, maintaining the gut microbiota's diversity and stability, supporting immune functions, and reducing systemic inflammation. However, exercise programs must be tailored to individual needs to avoid exacerbating IBS symptoms. Personalized exercise plans starting with low-to-moderate intensity and gradually increasing in intensity can maximize the benefits and minimize risks. This review examines the impact of various types and intensities of physical exercise on the gut microbiota in IBS patients, highlighting the need for further studies to explore optimal exercise protocols. Future research should include larger sample sizes, longer follow-up periods, and examine the synergistic effects of exercise and other lifestyle modifications. Integrating physical exercise into comprehensive IBS management plans can enhance symptom control and improve patients' quality of life.