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Exercisers are often told that muscle cramps are caused by lack of salt (sodium) or low potassium. However, recent studies show that athletes in endurance events who suffer cramps usually
have normal sodium and potassium levels. A review of the
current literature from Buenos Aires, Argentina shows that doctors don't know very much about exercise-induced muscle cramps (Journal of the American Academy of Orthopaedic Surgeons, July 2007). The most common cause appears to be muscle damage.
Athletes may be able to prevent cramps by slowing down when they feel the muscle pulling and tightening, and picking up the pace only when the muscle feels good again.
Cramps may occur as a side effect of drugs used for high cholesterol, high blood pressure or diabetes. Oral contraceptives, various other drugs or alcohol can also cause muscle cramps. If you suffer from recurrent muscle cramps that cannot be explained, check with your doctor. Possible causes include pinched nerves, Parkinson's disease, hypothyroidism, diabetes, narrowed arteries, low blood mineral levels, or metabolic diseases that cause muscle damage. However, most exercisers who experience exercise- associated muscle cramps do not suffer from disease and can usually prevent cramps by slowing down when their muscle start
to feel tight. Athletes are usually not willing to do this during
competition, so they will continue to suffer from occasional cramps and work them out as they occur.