Training and IBS: Avoid stomach problems


Do exercise and IBS go together? The importance of exercise is a widely known fact and is not something new. By exercising, one could clear the mind and straight after, it often feels as if the body gained new energy. The gastrointestinal tract also benefits from exercising and consequently, feels good from exercise because movement stimulates natural bowel movements. Though, at the same time, people often hear about stomach problems in sports, for example, according to this report that Carl-Christian “Calle” Halfvarsson dropped out of the Tour de Ski due to his IBS.

Even if you do not compete at a professional level, having stomach problems can be quite difficult during a training session, especially for the ones with IBS.

Runner’s stomach – why do athletes often have gastrointestinal complaints?

A 2017 study published at Monash University showed that no matter how fit the individual is, there is a limit to how much physical stress the gastrointestinal tract can withstand before disorders occur. Exercising intensively for over two hours at a time can cause stomach problems, and running and training in hot climates are listed as factors that can trigger the problems further.

This can be compared to “runner’s stomach”, which affects many people who participate in endurance sports, such as marathons. These are gastrointestinal problems that occur in connection with strenuous physical exercise. These gastrointestinal disorders are particularly common among young women. The intestines, unlike the body’s muscles, have difficulty adapting to increased mental and physical stress.


A runner’s stomach is characterized by the fact that the symptoms occur temporarily during training and disappear when you have finished training. If the symptoms persist even between training sessions, it may be another gastrointestinal disease, and a doctor should be consulted. Although the symptoms themselves are not dangerous (apart from severe diarrhoea which can cause dehydration), they can be difficult to deal with, especially when the focus is precisely on performance. The most common symptoms are:

  • Nausea
  • Abdominal pain
  • Vomiting
  • Acid reflux
  • Diarrhea
  • Bloating
  • Stomach cramps
  • Blood in the stool


The causes of runners’ stomachs are both mechanical and hormonal. When the body is in motion, stress is caused by the gastrointestinal tract, which redistributes the contents of the intestine. If the intestine is then filled with faeces, the intestinal emptying reflex is created, due to the increased pressure (it is, therefore, advisable to visit the toilet before the training session). When the muscles work, the blood (and oxygen) is redirected from the intestines to the skeletal muscles and results in low oxygen content (hypoxic stress) in the intestinal muscles. Hormones are released and further stimulate the gastrointestinal tract. The hormonal increase leads to increased secretion, ie secretion of fluid, which in turn causes watery diarrhea. During endurance sports, such as long-distance running, this can also cause dehydration.

If you already suffer from gastrointestinal problems, these can get worse in combination with hard training. These are mainly inflammatory bowel diseases such as Crohn’s disease and Ulcerative colitis, which increase the body’s demands for healing, but also for energy supplements, as an inflamed intestine has more difficulty absorbing nutrients from food. The effect can be an aggravated condition of the intestine and poorer performance in sports. It is not uncommon for gastrointestinal diseases to make their debut in connection with increased exercise.

Treat a runner’s stomach

What do you do about a runner’s stomach? Diet affects the gastrointestinal tract and is A and O to prevent intestinal problems during physical exercise and enable increased performance.

Because the symptoms vary from person to person, there is no one-size-fits-all solution. First of all, an examination by a doctor is required to rule out that the problems that arise are not caused by any disease. Once you have done that, you can review the symptoms and try to treat them in combination with slowly stepping up the intensity of the training based on a tailored schedule.

Exercise and IBS – does it help or upset?

Even if you do not suffer from a runner’s stomach, exercise and IBS can be a difficult combination. The vast majority feel good about exercising, but it can be much more challenging for those who suffer from IBS. If you suffer from diarrhea, the focus can end up on the proximity to the toilet, or you may fear getting stomach cramps during the workout. If you are constipated, exercise is especially good, as the intestines are stimulated and the stomach is kept going. On the other hand, bowel movements can cause pain.

Research shows that those suffering from IBS and inflammatory bowel disease benefit from low to medium intense physical activity. However, it has not been possible to determine how these diseases are affected by more strenuous exercise.

Our tips

As always, moderation is best, especially when it comes to exercise and IBS. Although exercise makes us feel good, it is advisable to pay attention and adapt the training to your specific, individual needs, symptoms and your daily routine. Exercise in a way that works for you and your stomach. Be kind to yourself and accept that sometimes it is not possible to train as you intended.

A 30-minute walk works just fine. If you are very stressed, calmer exercise such as pilates or yoga may be better suited, as high-intensity forms of exercise can stress the body further.