Cramp and stitch

The following is an article from the Strength and Conditioning Journal: Vol. 25, No. 1, pp. 47-48, by David Lapoff.



Cramping and Endurance Exercise

David Lapoff, ACSM HFI, CSCS
Lion’s Fountain Personal Training Honeoye Falls, New York

CRAMPING IS A PROGRESSIVE or acute involuntary contraction of a muscle that is usually painful, sometimes exquisitely so. The pain can destroy performance, sometimes for several days after the incident. Strategies for achieving top performance have to include strategies to reduce the frequency and intensity of cramping. Common victims of cramping include the calves, hamstrings, and diaphragm/abdominal wall cramp commonly referred to as the “stitch.”

There are 2 theories of muscle cramping. The so-called South African theory holds that poor exercise technique results in a lack of stimulation of the golgi tendon organ (GTO) allowing the muscle to progressively tighten into a spasm (5 , 6 , 8 ). Recall that the GTO is a proprioceptor in the muscle tendon that detects excessive tendon tension and relaxes the muscle. This counters the action of the muscle spindle that tightens the muscle when it is rapidly stretched. The other theory suggests progressive sodium losses from sweating (or limited intake) make nerves hyperexcitable causing the muscle to spasm (2) . There is good observational data from both camps, which makes this author believe (as with most either/or questions) that the truth is probably a combination of both causes.

Morton and Callister studied the abdominal stitch (4) and found frequency and intensity to be unrelated to the fluid or food consumed. Rather it is believed that diaphragmatic tugging on the abdominal wall provokes the spasm. This seems likely because tugging may provoke the stretch reflex of the abdominal muscles. Another phenomenon described by athletes as a “stitch,” is a trapped air bubble in the gastrointestinal tract. Sloppy drinking during an event or training can cause the swallowing of air into the stomach. Arising from the heightened excitement of competition, it is relieved quickly by a position change (e.g., lying down) allowing the air bubble to escape.

Because avoidance of cramps is the best defense, considering the theories of their development gives us an insight into how to prevent and deal with them. If we subscribe to the “South African theory,” then we should focus the client on the portion of the sport skill that lengthens the at-risk muscle when they feel the cramp beginning. (e.g., heel strike with pronounced dorsiflexion for the gastrocnemius, butt kick for the quadriceps, increased stride length for the hamstring).

If sodium losses are the suspected cause of the cramping, attention must be paid to the athlete’s intake of sodium both habitually and during the endurance event. Plain water is therefore not the beverage of choice during a long endurance event. The hydration plan for the athlete should include sufficient calories and electrolytes to replace those lost to exercise (1).

Measuring an athlete’s sweat rate is the first place to start when concocting a hydration solution. Once the quantity of sweat loss is known then the losses of sodium and other electrolytes can be estimated. Normative sweat contains approximately 35 milliequivalents of sodium. This corresponds to approximately 2 g of NaCl dissolved in a liter of water.

Cystic fibrosis (CF) is a risk factor of which trainers should be aware. Approximately 1 in 20 Caucasians possess 1 CF gene. This can lead to sweat with higher concentrations of both sodium and chloride. Seventy to eighty milliequivalents is not uncommon for these people (2) . Signs that this may be an issue for a client include caking of salt on the skin or sweat that burns the eyes. Consider referring these clients to their physician for testing. A hydration solution this salty may be unpalatable and so the use of salt tablets may be helpful in this case. It is most imperative that profuse sodium excreters do not use plain water as their hydration fluid because this can lead to hyponatraemia, which can be serious enough to be fatal.

Several approaches for relieving the stitch are put forward. Noakes recommends changing the stride/breath relationship so that the diaphragm is in a different relative position during the stride cycle. This presumably changes the location of tugging and reduces the stimulus to cramp. Noakes also recommends diaphragmatic (“Belly”) breathing to prevent the development of the stitch (7) . This author has had positive results with focused training of the abdominal muscles, particularly the obliques, reducing the frequency and intensity of abdominal stitches.
Abdominal “cramps” due to air ingestion can be avoided by concentrating on avoiding air intake while drinking and consciously attempting to evacuate any swallowed air immediately after taking a drink.

When is a cramp not just a cramp? One dangerous condition for which a responsible trainer or coach should watch is the sickle cell trait. Those with sickle cell trait (1 in 12 with African or Caribbean heritage, 1 in 10,000 in Caucasians) may not have the symptoms of sickle cell anemia but under high-intensity exercise conditions experience sickling, impeding blood flow. The result is exquisite pain dropping the athlete to the ground. These episodes usually occur at the beginning of the workout during a sustained, high-intensity effort and do not include a loss of consciousness. Keep this athlete well hydrated and arrange for him/her to see a doctor immediately. This kind of event can lead to rhabdomyolysis (muscle damage), which can cause kidney failure and death. To minimize this possibility, avoid sustained maximal efforts (e.g., 800-m wind sprints) and keep the athlete well hydrated (3) .

Cramping is a performance-sapping, painful event for an athlete. The diligent coach or trainer will help the athlete develop strategies for avoiding them. Electrolyte replacement and scrupulous exercise technique are the keys to avoiding skeletal muscle cramping. Abdominal wall strength, breathing, and drinking techniques all serve to affect the frequency and intensity of exercise-related abdominal pain.


1. Bergeron, M.F. Sodium: The Forgotten Nutrient. Sports Science Exchange. V13:(3) Gatorade Sports Science Institute. 2000.

2. Eichner, E.R. Cramps-management and prevention. Presented at Ironman Sports Medicine Conference. Kailua-Kona, HI. 2001.

3. Eichner, E.R. Rhabdomyolosis-the spectrum the spectre. Presented at Ironman Sports Medicine Conference. Kailua-Kona, HI. 2001.

4. Morton, D.P., and R. Callister. Characteristics and etiology of exercise-related transient abdominal pain. Med. Sci. Sports Exerc. V32:(2)432-438. 2000.

5. Noakes, T.D. Fluid and Electrolyte Disturbances in Heat Illness: Implications for Emergency Management. Trauma Emerg. Med. June/July 1998.

6. Noakes, T.D. Heat disorders in athletes. Presented at Ironman Sports Medicine Conference. Kailua-Kona, HI. 1998.

7. Noakes, T.D. The lore of running. Human Kinetics. Champaign IL. 1991. pp. 194-195.

8. Schwellnus, M.P. Skeletal muscle cramps during exercise. Physician Sports Med. V27:(12) 1999.

David Lapoff is a personal trainer and is certified by the American College of Sports Medicine and the Aquatic Exercise Association.