Your body’s clear signal that it’s time to lighten up your exercise regimen

Remember those terrible side pains called “side stitches” that you got as a kid when you ran too hard? (They can also occur when you laugh long and hard. After all, humor can be “side-splitting” or “leave you in stitches.”) 

Well, the actual medical term for a side stitch is: “exercise-related transient abdominal pain” (ETAP). I remember getting it often as an adolescent. And my daughter complained about it, too, when she was a child.  

Of course, most gym teachers or coaches would typically just brush off your concerns and say, “walk it off” or “grin and bear it.” But did you know that ETAP can actually affect elite athletes and weekend warriors, too? 

Unfortunately, like many common medical problems, there’s been very little research into ETAP. So, let’s take a look at what we do know—and how you can comfortably add exercise into your routine, without “side stitches”… 

Zeroing in on the cause of side stitches 

In 2015, researchers published some basic findings about this condition in the scientific journal Sports Medicine 

Here’s what we already know about ETAP… 

  • It’s more common in younger people, and the number of reported cases drops off as people get older. 
  • The pain is more common in exercises that involve twisting of the mid-section, such as horseback riding, running, and swimming.  
  • All kinds of people who engage in vigorous exercise can experience ETAP, but elite athletes experience it less frequently. 
  • Athletes tend to think it’s caused by eating or drinking before exercise, and some studies back up that theory. For example, lab studies show that drinking liquids with high sugar is more likely to cause ETAP than drinking liquids with little or no sugar. (Yet more bad news for so-called “sports” and “hydration” drinks!) 
  • Body type, body mass index (BMI), or sex are not found to be factors. 

One common theory posits that vigorous exercise impairs the delivery of blood and oxygen to the respiratory diaphragm, which causes side pain. (It’s a process similar to angina pectoris—where people with heart disease who exercise heavily suffer insufficient blood flow to the heart muscle, which causes acute chest pain.)  

And in my view, this theory makes a lot of sense…especially considering the major arteries that supply blood to the gastrointestinal (GI) organs run right through delicate stalks of connective tissue attached to the back of the abdomen. So, when you overtax yourself or twist and contort these tissues, it may cut off blood flow, causing pain.  

Perhaps, we should call ETAP angina abdominalis, as we do with chest pain from the heart. It certainly is abominable!   

As always, let moderation be your guide 

In the end, all these theories just lend more support to my long-standing advice to avoid overtaxing yourself with vigorous, grueling exercise. As I regularly report, excessive exercise (or “excess-ercise” as I call it) can cause great harm to your body and long-term health, including harm to your joints, heart, GI system, genito-urinary tract, and even your eyes! 

So, continue to let moderation be your guide when it comes to exercise. Aim to spend just 140 to 150 minutes weekly engaged in light-to-moderate physical activity.  

And now that we’re into June, the weather outside can be quite delightful for some nice, gentle, comfortable walks, hikes, swimming, and gardening in Nature…which all count toward your weekly total—and shouldn’t cause you any painful “side stitches”!  In fact, I report on my 5-top tips to keep you moving, comfortably, no matter what your age in the June 2019 issue of my Insiders’ Cures newsletter (“Your warm weather guide for safe and effective outdoor exercise”). So, if you haven’t already, consider becoming a subscriber today. Click here now! 


“Exercise-related transient abdominal pain (ETAP).” Sports medicine (Auckland, N.Z.), 2015; 45(1), 23–35.