I Googled 'Running stitch' this is what I got.

Today we have a first on RunningPhysio – our first blog from a chiropractor. Dr AJ Gregg is the head chiropractic physician at the Hypo2 High Performance Sport Centre in Flagstaff, Arizona. He has a wealth of experience and works with a team of professionals providing a host of services for elite athletes. Last year Hypo2 had 43 training camps with teams from 15 countries including over 650 athletes, coaches and support staff. I'm very grateful to AJ for sharing some of his knowledge and experience with us. He's written a very comprehensive post on 'side stitch' so I've included a key point summary at the end of the article for those just looking for a couple of tips. Over to AJ…

Abdominal pain is a common complaint among runners and other endurance athletes and can hinderer athletic performance. The uncertainty associated with pain that appears unexpectedly and cannot be successfully treated may erode the self-confidence of the athlete and seriously affect athletic performance. A stitch at the wrong moment may make the difference between winning and losing. While the mater can be complex this post is an attempt to draw the athlete and the therapist into correcting the most known factors.

The differential diagnosis of abdominal pain in athletes can range from muscle cramps, median arcuate ligament syndrome, GERD, ulcer, costochondritis, mesenteric ischemia, cholecystitis, pleurisy, and gastritis. A thorough workup to rule out all other pathologies is warranted to CYA (cover your ass) and then the complex workup of side stich can begin. I will refer to side stich by its medical classification of Exercise Related Transient Abdominal Pain (ETAP). ETAP may be severe, recurrent, and resistant to treatment. In one year of training 69% of runners with experience this syndrome. There is no direct evidence of the cause of this phenomenon.

ETAP is a common complaint in activities that involve considerable torso movement such as running and swimming. For most it is well localized pain related to exercise and may occur in any region of the abdomen. It is most prevalent on the lateral side of the mid abdomen, mostly on the right. Runners usually describe the pain as sharp or stabbing when severe or cramping pulling or aching when less intense. Exact mechanism of pain is unknown though many theories exist. There is an association with shoulder tip pain, a referral pain pattern from the diaphragm, so shoulder tip pain with the complaint suggests diaphragmatic involvement. One proposed theory is lack of blood flow to the diaphragm. Other theories include stress on visceral ligaments, muscular cramps, or Irritation of parietal peritoneum arising from friction between parietal and visceral folds.

Risk factors for ETAP are eating or drinking before exercise. Specifically beverages with high carbohydrate content or high osmolarity are linked to the condition. Consuming fatty foods or dairy products prior to sporting event, consuming large mass of food relative to body weight 1-2 hrs prior to event, high exercise intensity, cold conditions, lack of warm up, and individuals with increased kyphosis also increase the risk of the condition.

Most of the athletes who walk into my door have already examined the former of the above. While I do pre-screen and rule out any food or drink related problems, most all athletes have exhausted their options, such as patients do in the age of google and ‘trying to fix-it-youself’. I have found that elite runners usually do not get side stich due to the above because they are typically more experienced on how to eat better around their running and control their breathing, but it has little to do with their training status. However the foundation of the treatment protocol is to still address nutrient timing and breathing.

Next up is thoracic kyphosis – or as I look at it restricted thoracic extension (and I’m throwing rotation in as well) or mobility.

If there are no symptoms outside of exercise induced pain, relieved with cessation of activity I usually make the diagnosis from the history. An abdominal exam is usually unremarkable (or I make a referral because an abnormal abdominal exam suggests different etiology of pain during exercise).

Acute treatment during the attack is to stretch the affected side, bend forward, and to take deep breaths, as well as pushing on the affected side. When one is trying to run, the later works best.

The Prognosis is not well documented. Decreased frequency is noted with improved training status and age. Most likely secondary to acknowledgment and avoidance of precipitating factors.

Because ETAP can be an enigma we will talk about the more recently investigated factors that have been identified or proposed as the cause of abdominal pain during exercise and how they may apply to treatment. The most frequently mentioned are mechanical trauma with injury of the intestinal mucosa, hypertrophy of the psoas muscle with compression of the gastrointestinal tract, bloating, hollow viscera spasm, abdominal wall cramps, intrapelvic muscle strain, caecal slap syndrome (repeated trauma of the caecum against a hypertrophied muscular wall), ulceration of the gastric and duodenal mucosa caused by ingestion of non steroidal anti-inflammatory drugs, motility disturbances resulting from a diet rich in carbohydrate and fibre, extreme mobility of a kidney, irritation of the parietal peritoneum, and an exertion related reduction in the washout of substances with an osmotic effect in the intestinal interstitial fluid.

WOW. Are you overwhelmed, because I am. . .?!

But let’s start from the top and work our way down on EVERYTHING that can be done:

Nutrient timing:

As suggested by a number of the theories proposed above, the weight of the organs of the abdominal cavity could lead to cramping or stitch. Thus the solution offered by various authors is to use fluids in small frequencies rather than a large volume at once while exercising. Also suggested is to consume drinks with small carbohydrate content (hypotonic) as they have been shown to be absorbed faster, thus reducing the weight of the gut. Avoid eating a large meal prior to exercising or high fat foods, as they take longer to empty from the intestines as well. The fluids in order of increasing osmolarity are no fluids, water, energy drinks, Coca-cola, and Duphalac (a solution of the sugar lactulose). This suggests that hypertonic fluids may play a role in ETAP during sustained bouts of exercise, so it’s best to avoid them if your experiencing ETAP.


Breathing exercises and proper breathing technique is one important concept for those susceptible to ETAP. Respiration patterns play a huge role in not only cramping, but also many biomechanical factors in the skeleton and muscles of the thorax, spine and even neck. Exercises designed to encourage abdominal breathing and facilitation of the diaphragm, such as Blowing up the Balloon, rather than upper chest breathing can rehabilitate a number of specific pain patterns. Pursed lip breathing while running has also shown to help reduce stitch pain in some cases.


Mobilizations to the thoracic spine in patients with decreased range of motion may help rule out the involvement of stitch pain in some patients affected by the thoracic spine pain referral theory. Back in 2004 D P Morton published a letter in the British Journal of Sports Medicine suggested that the stich effect could be induced by palpating vertebrae T8-T12 (lower part of the thoracic spine – pretty much middle of the back and connected to abdominal muscles). Trying to figure out why thoracic issues might be the cause, the authors note,

“The extent to which the thoracic intercostal nerves may contribute to the experience of ETAP is worthy of further investigation. It seems plausible that, in some cases mechanical compression of the nerve root may refer pain distally, resulting in abdominal pain.”

From a mechanistic viewpoint, increased curvature of the thoracic spine could influence the experience of ETAP either functionally and/or neurally. Functionally, kyphosis could affect rib cage mechanics, conceivably placing atypical stresses upon other abdominal structures (though this has been discredited.) From a neural perspective, the abdominal region is innervated by spinal nerves arising from thoracic vertebrae T7-T12. Notably, abdominal pain similar in nature to ETAP has been evoked by lesions and compression of these spinal nerves. Further, I have been able to reproduce symptoms of ETAP by palpating sites adjacent to T7 through T12. Oh the many ways the body refers pain!

I always assess thoracic spine mobility standing and seated with global extension and rotation. With rotation I am looking for 30 degrees to the right and left and standing extension should show a uniform thoracic curve and the spine of the scapula clearing the heels. Any dysfunction due to lack of mobility or motor control I treat. Home care mobilizing with a foam roller or a peanut (made of two lacross balls taped together) has yielded great results as well as manual therapy to the involved areas. If there is referral ischemic pressure until it dissipates helps the condition greatly, this can be done with a therapist or by the patient with a lacrosse ball.

Relieving quadratus lumborum (QL) or psoas muscles restrictions can also cause relief if the mechanism of the stitch is caused by the tightness in these muscles. I test the QL for restriction by examing lateral bending and treat the restriction with manual therapy. I have also found that if their endurance in side bridge is less than 90 seconds that improving the endurance of the muscle leads to less hypertonicity or tightness.

If there is a positive Thomas test or a notable tightness side to side, a trial of stretching of the iliopsoas is warranted. If nothing else is working, this should be investigated. I have also found that this muscle tends to produce symptoms near its attachments to the lumbar vertebra, so skilled manual therapy is necessary, and the patient should be comfortable with deep palpation into the abdomen. It should be noted that there is considerable debate over whether the psoas can be palpated in this way.

Lastly it is my opinion that intercostal muscles and the diaphragm itself be investigated for restrictions in mobility, function, and tenderness. Any abnormal findings should be investigated and treated accordingly.

There is much research to be done on the musculoskeletal components of such a common injury.

Mental/Psychological factors

Many athletes believe that abdominal pain and other symptoms may be aggravated by anxiety and precompetitive psychological stress. Progressive muscle relaxation techniques help and for some using a biofeedback device such as Heart math to reduce sympathetic activity can help.

Addressing Ischemia or hypoperfusion:

One theory postulates that abdominal pain is caused by shunting of blood from the splanchnic bed and diaphragm to the limbs during exercise, and several studies have shown a reduction in blood flow during exertion. This may lead to hypoperfusion and ischaemia of the viscera or diaphragm and generate pain. This is one of the most accepted etiological theories for exercise related abdominal pain. However, ischaemia does not explain many of the clinical findings. Furthermore, the results of a recent study suggest a lack of correlation between the reduction in abdominal blood flow and pain during effort. Origins of this theory are rooted in the referral of the diaphragm to STP and the subjective association of eating and drinking and increasing intensity (increased respiration) with ETAP, and the most common location of ETAP being the periumbilical/sub-diaphragmatic regions.

Asprin works by thinning the blood, modulating inflammation, and improving mitochondrial function to an extent and Non-steroidal anti-inflammatories (NSAIDS) help decrease inflammation that may be associated with the condition. I recommend a one week trials of each before runs to determine which helps best and the mechanism involved. I advise against long term and chronic use due to the side effects and inhibition of training gains. Once an appropriate dose and medication has been determined I advise that they only be used before big races or as needed for workouts. I have a protocol(which includes glutamine and other gut healing agents) for combating the gastrointestinal induced problems from endurance training, though I have seen its efficacy for aiding in ETAP to be minimal.

Biomechanical factors:

The pounding effect of intestinal jarring has been considered a direct cause for the development of gastrointestinal symptoms during running. Mechanical stimulation of the intestinal mucosa during running may result in a release of vasoactive intestinal peptide (VIP) and prostaglandins, which promote colonic contraction and could cause abdominal cramps and secretory diarrhoea. Finally, the higher prevalence of abdominal pain in runners than in participants in other endurance sports suggests that mechanical strain on the viscera plays a role in the genesis of this disorder. After long exertion, occult blood has been detected in the stool of up to 87% of participants in endurance events. In another study, endoscopic examination revealed upper gastrointestinal lesions in 15 of 16 runners after a 20 km race. While this may or may not lead to ETAP its investigation may warrant evaluation if other methods do not work and specific gastrointestinal aids shown to be effective in athletes may be effective.

Run Softer: One of the simplest ways to change the loading rate (or tibial shock) in runners is to simply instruct them “To run softer“. Isn’t that awesome? Just let the runner figure out a way. Some runners might shift to a forefoot strike, some might heel-strike but they will find a way to make less noise and run softer.

Generally, abdominal pain resolves when the effort is stopped or when techniques such as bending forward while tightening the abdominal muscles or breathing through pursed lips after a deep inhalation are applied. Bending forward while tightening the abdominal muscles – pull the ribs down NOT THE STOMACH IN – also facilitates the deep core (multifii, transverse abdominals, diaphragm, and pelvic floor) as researched by spinal expert Stuart McGill, may help.


It is my opinion and clinical experience that after other biomechanical, structural, mental, breathing, and nutrient timing factors have been ruled out that dietary triggers should be investigated. I have had three high level athletes with ETAP unresponsive to the measures listed above do an elimination diet with success. Common triggers include dairy, wheat, corn, soy, citrus, milk, eggs, nuts, and shellfish. These food sensitivies do not appear to be IgE related, so an elimination and challenge diet is warranted as the gold standard. Athletes were instructed to remove all foods and challenge one at a time and wait for 72 hours for symptoms to appear. If no symptoms then the athlete can add the food back in. If symptoms arise they remove the food and try to rechallenege in six months.


Abdominal pain during strenuous physical exertion usually has a functional cause and is not related to an underlying disorder. The etiology of abdominal pain during exercise is often difficult to determine as the complaints are only present during exertion, and between pain episodes the patients have no signs of disease. Usually the symptoms are self-limiting and only require symptomatic treatment. However, they may be frustrating for competitive athletes and they may prevent them from achieving optimal performance during competitions.

Furthermore, some circumstances suggest that the cause of pain is not functional. New complaints during exertion in an experienced and previously asymptomatic athlete, the absence of triggering factors such as trauma or dietary excesses, a change in the pattern, duration, or severity of pain, or the persistence of symptoms after exertion all suggest an underlying disorder. In such cases, basic diagnostic work up should include physical examination, blood count, measurement of hepatic and pancreatic enzymes, and ultrasonography. A history of postprandial complaints, heartburn, or recurrent pain episodes associated with a positive faecal blood test should be pursued by gastrointestinal endoscopy. Computer scans may help to rule out less common causes of abdominal pain such as neural compression, bone and spine disorders, and intra-abdominal masses. One report in the literature suggests that gastric tonometry may help diagnosing and grading gastrointestinal ischaemia during exercise. Finally explorative laparoscopy is only justified when all the causes of abdominal pain mentioned above have been ruled out, but it has found to be diagnostic in one report in the literature.

Author: Dr. AJ Gregg, DC, CSCS, MS, & Wes Gregg, DC, Hypo2 High Performance Sport Center – Flagstaff, AZ

Follow AJ on Twitter via @dr_ajgregg


1. Morton, Darren P, Callister, Robin. Factors influencing exercise-related Transient abdominal pain. Medicine & Science in Sports & Exercise. 2002; 34 (5): 745-749.

2. Morton, Darren P. Exercise related transient abdominal pain. British Journal Of Sports Medicine. 2003; 37 (4): 287-288. http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1724690&;blobtype=pdf

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4. Morton, Darren P, Luis, Fernando Aragon-Vargas, Callister, Robin. Effect of Ingested fluid composition on Exercise-related transient abdominal pain. International Journal of Sport Nutrition and Exercise Metabolism. 2004; 14: 197-208.

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