Diaphragm cramping can quickly ruin your racing experience. When pain grips your upper abdomen, it's hard to focus on the race or your time. The problem is particularly common for new runners still adjusting to the rigors of running. Making changes to your running form and routine can help reduce diaphragm cramping.
Diaphragm cramping, also called a side stitch or exercise-related transient abdominal pain, occurs when painful spasms affect your diaphragm. Pain may be felt on one side or under the rib cage. The diaphragm is a muscle found in the chest cavity under your lungs. When you breathe in, the diaphragm tightens and moves downward, expanding the chest cavity and allowing the lungs to take in air. When you exhale, the diaphragm relaxes and moves upward, forcing air out of your lungs.
The American Council on Exercise reports that it has been hypothesized that side stitch pain is caused by the jarring and pulling on the ligaments that attach the stomach to the diaphragm. The problem may be more likely to occur if you run soon after eating because a full stomach may irritate the diaphragm when you run. Spasms can also occur if you breathe rapidly during a long race, causing the diaphragm to work harder. Dehydration can worsen the problem, as can a change in your running form. Leaning forward when you run may strain the chest muscles, causing pain and spasms.
Using abdominal breathing while running may be helpful in reducing diaphragm cramping. During abdominal breathing, you inhale slowly through your nose, hold your breath for several seconds and breathe out through your mouth. As you inhale, you push your abdomen out and relax it again when you exhale. Deep breathing while keeping your lips pursed may also help. Pursed breathing involves inhaling through the nose and exhaling through the mouth while keeping your lips together as though you are whistling.
Although eating shortly before a race isn't a good idea, neither is drinking an entire bottle of water or a sports drink. You can stay hydrated and reduce your chance of developing a side stitch by drinking small amounts of fluids while you run, rather than drinking a large amount at one time. Choosing drinks with a low carbohydrate content will cause faster absorption and decrease the effect on your stomach and diaphragm. An April 2004 study published in the "International Journal of Sport Nutrition and Exercise Metabolism" found that athletes who drank reconstituted fruit juices and beverages high in carbohydrates shortly before and during exercise experienced increased exercise-related transient abdominal pain.