Irritable bowel syndrome: prevention, diagnosis, and when to see a doctor

Irritable bowel syndrome is not life-threatening, but it is capable of ruining training, competitions, and daily well-being. The good news is that most people with IBS can substantially reduce their symptoms. The bad news is that other diseases sometimes hide under the mask of IBS. Our editors explain how to approach the prevention of flare-ups, how doctors make the diagnosis, and which signs mean it is no longer 'just a sensitive gut.'

Preventing flare-ups: routine, stress, training

The guidelines of the British Society of Gastroenterology (2021) and the American College of Gastroenterology (2021) put general measures first: regular meals, sufficient sleep, physical activity, and working with stress. For athletes these recommendations need to be adapted to the training schedule.

Regular moderate activity is not an enemy but an ally in IBS. Problems usually arise at the peak of loads, during competitions, and in periods of sharp dietary changes. That is why planning is important: intense sessions not immediately after eating, a sufficient interval between the main meal and the start, a predictable 'toilet' route on long workouts.

• the main meal 2–4 hours before intense training;
• before the start — familiar foods, no experiments;
• practicing feeding during prolonged work in advance;
• controlling hydration, especially in the heat;
• relaxation and breathing techniques before competitions.

Stress and anxiety substantially affect symptoms through the 'brain–gut' axis. Sports psychologists work with pre-start anxiety; in pronounced IBS, cognitive behavioral therapy and gut-directed hypnotherapy have proven effectiveness.

A symptom diary is a simple but very effective tool. By recording food, supplements, training, sleep, and symptoms over several weeks, you can identify personal triggers that are not visible 'at a glance.'

Nutrition: the low-FODMAP diet and sports products

The low-FODMAP diet is the most studied dietary approach in IBS. It consists of three stages: restricting high-FODMAP foods (usually for 2–6 weeks), gradually reintroducing individual groups to identify triggers, and a personalized long-term diet.

It is important that the goal is not a lifelong strict diet but finding individual triggers. Prolonged unjustified restriction can worsen the microbiota and the completeness of the diet, which is critical for an athlete because of the increased need for energy and carbohydrates. Therefore it is optimal to go through the diet under the supervision of a dietitian.

Soluble fiber (in particular psyllium) has proven benefit in IBS and is recommended by guidelines, whereas insoluble fiber (bran) can increase bloating. It is better to increase the amount of fiber gradually and not on competition day.

As for probiotics, the guidelines assess the evidence as limited: individual strains may help individual people, but there is no general recommendation. A sensible approach is to try one product for a defined period and stop if there is no effect.

Diagnosis: how IBS is diagnosed

IBS is a positive diagnosis, made on the basis of typical symptoms according to the Rome IV criteria, not just by 'exclusion.' However, a minimal examination is needed so as not to miss other diseases with similar manifestations.

The ACG and BSG guidelines recommend that most patients with IBS symptoms have a complete blood count, C-reactive protein, and serological screening for celiac disease. With predominant diarrhea, fecal calprotectin is often measured — a marker of inflammation that helps distinguish IBS from inflammatory bowel disease.

Colonoscopy in typical symptoms in young people without alarming signs is usually not performed routinely. It is prescribed in the presence of 'red flags,' a family history of colorectal cancer, in older age, or when microscopic colitis is suspected.

For athletes it is important to consider specific causes of symptoms: iron deficiency (which can be both a consequence and a cause of problems), lactase deficiency, fructose malabsorption, and intestinal infections after travel. The doctor may order breath tests or stool tests for parasites depending on the situation.

Treatment options

Treatment of IBS is built step by step and depends on the predominant type of symptoms. The first line is general measures, physical activity, dietary correction, and, if necessary, soluble fiber.

Medication options are chosen by the doctor. For pain and spasms, antispasmodics may be used (in particular, peppermint oil in enteric-coated capsules has confirmation in the guidelines); for diarrhea, loperamide for episodic use; for constipation, osmotic laxatives. For severe cases there are second-line drugs, including low doses of tricyclic antidepressants, which act as neuromodulators of gut pain sensitivity rather than as 'antidepressants.'

Athletes who plan to take loperamide prophylactically before a start should discuss this with a doctor in advance: the agent is appropriate episodically, but should not mask an undetected problem, and in the heat and with dehydration its use requires caution.

Psychological methods — cognitive behavioral therapy, hypnotherapy — have an evidence base and are considered by the guidelines as a full-fledged part of treatment, especially when symptoms are closely linked to stress.

When to see a doctor

Everyone with prolonged gut symptoms needs to see a doctor — if only to confirm the diagnosis and rule out other diseases. Self-diagnosis of 'I have IBS' without examination can lead to missing celiac disease, inflammatory bowel disease, or other conditions.

A consultation is needed immediately or as soon as possible in the presence of alarming signs that are not characteristic of IBS:

• blood in the stool or black stools;
• unexplained weight loss;
• symptoms that wake you at night;
• anemia, fever;
• the appearance of symptoms in older age or a sharp change in the usual character of the stool;
• colorectal cancer, celiac disease, or inflammatory bowel disease in the family.

Emergency care is needed in the case of severe abdominal pain with fever, repeated vomiting, signs of dehydration after an intestinal infection, and also bloody diarrhea — especially after a long event in the heat, when ischemic bowel injury is possible.

During the visit it is useful to have a symptom diary and a list of all supplements, sports products, and medications. This helps the doctor distinguish IBS from food intolerance more quickly.

Editorial conclusions

Preventing IBS flare-ups in athletes combines an eating regime around training, working with stress, and searching for individual triggers — in particular among sports products.

The low-FODMAP diet is effective, but works best as a temporary diagnostic tool under the supervision of a dietitian, not as a lifelong restriction.

The diagnosis is made by the Rome criteria, but a minimal examination — a blood test, CRP, screening for celiac disease, and if necessary calprotectin — is mandatory. Blood in the stool, weight loss, and nighttime symptoms are a reason for immediate attention.

We also recommend reading our articles on the causes of IBS in athletes and the role of pharmacology, on gastritis, and on choosing a protein with lactose intolerance.

References

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