ETAP – how does it develop and what can you do about it?

Imagine yourself running to attain your personal best over your preferred well-trained distance. With your mind’s eye, you can already see your excellent result and you cannot wait to start celebrating right after you cross the finish line, when suddenly, you feel a pang of acute, penetrating pain in your stomach. Exercise-related transient abdominal pain (ETAP) can thwart both amateurs and professional athletes in their efforts. Here are some tips for reducing the likelihood of experiencing this inconvenient condition.

28 August 2023

Exercise-related transient abdominal pain – the condition and its symptoms

As indicated, ETAP is an abbreviation used to denote short-lived transient abdominal pain caused by physical exercise.

The pain has an abrupt onset – it does not depend on the duration of the exercise or on the energy you have. It has nothing to do with your gender or body weight. It is most often experienced by people practicing relatively high-intensity sports, such as running, swimming or cycling, but also some disciplines which involve repetitive vertical body movements, such as fitness exercises, basketball or horse-riding.

Experts have so far been unable to unequivocally pinpoint the causes of ETAP. Due to the transient nature of this ailment, scientists must rely on the experience and accounts of individuals who have experienced ETAP. However, there are some hypotheses which bring us closer to discovering the potential root causes of the problem:

Reduced blood supply to the diaphragm – as blood is redirected to peripheral muscles during physical exercise, the diaphragm contracts and the ligaments which connect it to inner body organs such as the stomach, liver and spleen, become irritated. Irregular shallow breathing and repetitive vertical body movements exacerbate the pain.

Phrenic nerve irritation – mutual friction between the membranes lining the inside of the abdominal cavity irritates the nerve supplying the diaphragm. This hypothesis explains why shoulder pain accompanies some cases of ETAP – the phrenic nerve runs close to the neck area.

Body posture – ETAP has been more frequently reported in individuals with thoracic kyphosis (excessive backward curvature of the thoracic spine) and weak lumbar muscles.

There are several known facts which favor the development of ETAP. These are mainly related to the individual’s lifestyle and exercising practices. They include:

Having copious meals immediately before exercising – the moving gastric content and the ongoing digestion processes exacerbate diaphragmic discomfort;

Incorrect eating habits – too much food which is difficult to digest extends the period when the likelihood of ETAP is highest;

Too intensive exercise – too strenuous activity or starting from too intensive exercises speeds up anaerobic processes which may lead to pain;

Insufficient warm-up – as above;

Dehydration – insufficient amount of fluids may exacerbate abdominal discomfort. Notice: the same goes for exercising with an empty stomach!

Health conditions and medication – overall weakness and the side effects of medication may lead to the development of ETAP;

Strong stress – heavy strain on the nervous system promotes cramps and other types of pain and discomfort.

How to prevent ETAP?

Since ETAP has not been sufficiently studied, popular methods of avoiding the condition are of anecdotal nature and come from people who have experienced such painful episodes. Here are some methods which will not hurt, but may help you to prevent ETAP while running or doing other forms of physical exercise:

Prepare your body for physical activity – before your start working out, make sure you warm up thoroughly, and only increase the intensity of your workout gradually during the session.

Body posture is key – if you are practicing a relatively high-intensity sport discipline, find some time to train your postural muscles which are responsible for maintaining the right body posture.

Remember to use the right technique – an incorrect exercising technique while doing high-intensity workouts may lead to ETAP and other ailments. If you have any questions or doubts, consult with your personal trainer.

Do not exercise right after eating – many sources recommend waiting for 2-3 hours after a meal before you start exercising, but this is not a rule set in stone. The rate of digestion and metabolism is an individual matter and it depends on many factors. However, it is always a good idea to have some rest after a meal.

Avoid sugary drinks – it is better to have some water or an isotonic drink before, during and after a workout, rather than e.g. fruit juice.

What should you do when you feel ETAP?

ETAP is known to have a sudden onset. Even with the right physical preparation, you cannot be 100% sure that you will not get it when you least expect it. Fortunately, the pain is of a transient nature, which means that not everything is lost when you feel it. ETAP usually subsides within several minutes and athletes have come up with some practical ways to quickly cope with the symptoms:

Diaphragmic breathing – take several deep abdominal breaths to relax the diaphragm (for more about this topic, read the article: “Breathe to Relax and Cool Down – Learn 5 Techniques to Help You Do So”). You can also try another exercise: breathe in deeply, keep the air inside your lungs for a few seconds and then breathe out fully.

Apply pressure where it hurts – by applying slight pressure to the sore area with your fingers, combined with a slight forward leaning position of the chest, you may reduce the pain sensation. You can use this technique without interrupting your run.

Muscle stretches – run with your hands above your head and your fingers interlaced, or reach behind your head with one hand and slightly bend your upper body to the side to relieve strain on your abdominal muscles.

Go slower or stop – reduce exercise intensity or stop altogether to make ETAP go away in a matter of minutes. You can slow down, reduce your running speed to walking or simply stop for a while if you are in a lot of pain. When it goes away – gradually increase your speed back to the desired level. Remember about regular breathing!

Note: If you feel ETAP, DO NOT sit down, DO NOT squat and DO NOT assume any other body positions which may increase muscle tension. If ETAP does not subside after a long while or you feel any other symptoms (fever, edema, etc.) seek medical attention!

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_Resources:

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