The Dreaded Side Stitch: What Causes It and How To Prevent It

I’m proud to say that after many hours of training, I recently ran my first New York City Marathon. I’ve been a runner for many years, but I experienced something new — and quite annoying — during my training: the dreaded side stitch. As any nerdy dietitian with an education in sports nutrition and exercise physiology would do, I immediately hit the books to research the cause of and cure for for it.

What is a Side Stitch? 

As it turns out, it has a scientific name: exercise-related transient abdominal pain, or ETAP.  It's often described as a cramping, aching or pulling feeling at first, progressing to a sharp or stabbing severe pain in the lower abdomen. Are you wondering why I keep calling it a "stitch" rather than a cramp? Research has shown that the painful feeling in your side is actually not a muscular cramp.

Who Gets Side Stitches? 

Interestingly, side stitches occur most often in two types of athletes: runners and horseback riders. These activities involve repetitive torso movement, which causes side stitches more often. Certain demographics also have increased chances of feeling this pain:

• Age. Side stitches are much more likely to affect the young athlete. One study reported that 77 percent of active individuals under the age of 20 experienced ETAP, compared with only 40 percent of those over 40. Not only does the prevalence of side stitches decrease with age, but the severity decreases as well.
• Gender. One study reported that females experience side stitches four times more often than males.
• Fitness level. Well-conditioned individuals are less likely to experience ETAP, as compared to people that are physically unfit.

What Causes a Side Stitch? 

Unfortunately, the reason you feel abdominal pain during exercise is not entirely clear, but there are a few common theories:

• Bad posture. Studies have shown that people with poor posture are more susceptible to side stitches, and the worse the posture, the worse the stitch.
• Eating or drinking right before exercise. Consuming food or drink just before a training or workout session has consistently been reported to evoke ETAP. The good news is that you can teach your body to tolerate more fluids with practice.
• Irritation of the abdomen's lining, AKA the parietal peritoneum. This is the most widely accepted reason for a side stitch. Some scientists believe that the irritation occurs from friction between the lining of the abdomen and the abdominal wall. This friction happens when the stomach swells during exercise, due to an increase in the quantity or thickness of the stomach's lubricating fluids.

How to Prevent Side Stitches

Because scientists haven’t been able to figure out the primary cause of side stitches, it's difficult to determine a way to prevent them. However, these strategies seem to work for many people:

• Avoid large volumes of food and drink for at least two hours before working out. During exercise, take small gulps of water or a sports drink.
• Improve posture. A great way to improve posture is to do yoga or Pilates to strengthen your back and core muscles.

The most common techniques for getting rid of a side stitch are deep breathing, pushing on or stretching the affected area and/or bending over. Research has not confirmed that these strategies work, and some believe that bending over and stretching work against the problem and cause the stitch to continue. It’s best to use the strategies above, and just keep training for better physical condition.