Accordign to Ace Fitness, it is a myth that potassium deficiency causes cramps, since there isn't enough potassium in sweat to deplete potassium. Sodium deficiency is blamed instead. Is this true?

1 Answer 1


There is no single cause of cramps, but there are several known causes. Both WebMD and Ask.com have overlapping reasons.

  • Poor blood circulation
  • Overexertion of a muscle
  • Exercising in the heat
  • Dehydration
  • Potassium/Magnesium deficiency
  • Malfunctioning nerves

I remember reading a long time ago that it's less about a potassium/magnesium deficiency and more about an imbalance between those minerals and sodium. What the article you linked to fails to recognize is the involvement of those minerals in the muscle itself. It's not sweated out because it is used as your muscles work.

  • I'd say that there are several theorized causes. The kinesiology world is still not certain what exactly causes cramps. The deficiency compared to other electrolytes is one of the more popular theories, but none of them have been proven yet.
    – JohnP
    Apr 19, 2014 at 5:16
  • If it is happening often probably worth a visit to gp. Other causes are a build up of toxins and liver disease. So maybe try isotonic drink after exercise and keep hydrated, if this doesn't help. Get yourself checked out Apr 19, 2014 at 11:38
  • @JohnP, wouldn't kinesiology (the study of kinetic movement) be the wrong branch of science for determining the cause of cramps? If improving your hydration fixes the problem, then wouldn't that be enough for a layman's understanding of cause and effect? I don't think there is simply one cause of cramps, and they are simply a symptom of something else going on in the body. Hence the list of multiple potential causes. Apr 19, 2014 at 13:53
  • @BerinLoritsch - Maybe I use the term a bit oddly, but I use kinesiology as a blanket type description, as most colleges list the degree as exercise kinesiology which encompasses the physiology and mechanics of movement and sport. My only objection is the use of the phrase "several known causes". They are theorized causes, none of them have been proven yet.
    – JohnP
    Apr 19, 2014 at 15:53
  • @Tracyat2bactive - What "toxins"? How does liver disease cause muscle cramping? Do you have references for those claims?
    – JohnP
    Apr 19, 2014 at 15:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.