Runner's stitch is the one condition that almost certainly befalls every runner at some time in either training or competitive circumstances. Known as a side stitch, or by the technical term exercise-related transient abdominal pain, runner's stitch is a painful but entirely transient and correctable physical problem. There are many explanations tendered through sports science as to its cause.
Runner's stitch is a painful cramping or stabbing sensation that is experienced by a runner during the course of the activity. The pain usually is felt most sharply under the rib cage, in the vicinity of the diaphragm and upper abdomen. In some cases, the pain will also seem to radiate to the runner's shoulder. Sometimes, the stitch will either slow the runner or immobilize him or her for a brief period while he or she endeavors to recover from the effects of the stitch. Although precise data on the point has never been gathered, there is strong anecdotal evidence in the running community that suggests that runner's stitch is more common among inexperienced or novice runners than among veteran athletes.
While the stitch manifests itself as a cramp, the accepted possible causes of the condition are wide ranging. It could occur due to impaired blood flow, or ischemia, to the abdomen and diaphragm during exercise. Another condition is the irritation of the muscle walls of the abdomen through the repetitive movements of running (the nerve structure from the abdomen ultimately radiates to the shoulders, accounting for the sensation sometimes felt there with the onset of a stitch. Stress placed on the connective tissues that support the diaphragm through movement occurs when the athlete has been breathing quickly, introducing short or shallow breaths into the lungs, and the diaphragm muscles may become stressed. In a related fashion, it is also believed that running will particularly affect the ligaments that hold the liver in place relative to the diaphragm (the liver is positioned immediately below the diaphragm), the repetitive bouncing motion created by the running stride creates undue tension on these ligaments that may create a source of stitch pain. Another possible cause of runner's stitch is cramping or muscle spasm directly within the muscles of the diaphragm.
In addition to the causes that have been identified as the potential reasons for a runner's stitch, cold weather running is often cited as an aggravator of this condition, as is the consumption of food within one hour of a race or workout.
A runner's stitch can often be remedied during the course of the run. The most effective approach is to stretch the diaphragm structure, which may be accomplished in a number of ways. The first effective diaphragm stretch is alter the breathing pattern; short, shallow breaths place a different stress on the diaphragm than do deep regular breaths. Often, a period of slower speed running or walking while taking very pronounced deep breaths will correct a stitch.
Another effective treatment is the application of manual pressure to the affected area. While the runner slows to a walk, he or she can firmly grasp the location of the stitch below the rib cage, pressing hard into the abdomen. While pressing against the muscles, the runner may then bend at the waist briefly to generate further pressure on the stitch location. The combined effect of the manual pressure with that of the bending of the runner's body often provides an immediate remedy that will permit the runner to resume the pace without recurrence of the stitch.
Biomechanical studies reveal that most runners instinctively coordinate their breathing with the rhythm of their foot strike. When the runner makes a deliberate effort to ensure that the inhalation and exhalation of breath are coordinated with their footwork, the diaphragm will then move in a more synchronized fashion with the body and be less likely to bounce as the runner moves, thus reducing any additional stress on it or the connective tissues that support it.
As with any other type of muscle difficulty, the overall strength of the abdominal muscles may contribute to the formation of a runner's stitch; improved overall fitness is the best prevention for runner's stitch. The runner's stretching program should include exercises directed to the lumbar (low back) and abdominal muscles, which ultimately support the efforts of the diaphragm.