Potassium is important in nerve function by allowing muscle contraction of all nerve impulses sent by action potentials. Potassium also influences osmotic balance between cells and the interstitial fluid.

Sodium is reabsorbed to keep the blood volume exactly right and the osmotic pressure correct while potassium is reabsorbed to keep serum concentration correct.

Potassium deficiency can be caused by diarrhea or repeated vomiting in both athletes and non- athletes, the most common cause of low potassium blood levels and high potassium urine levels is vomiting.

Potassium loading with athletes has been researched to find that the kidneys and sweat glands conserve potassium effectively in response to low body levels that potassium deficiency rarely occurs.

However potassium levels in blood plasma, urine, and feces during Hyperkinesias with the presence of potassium deficiency suggests that the body has an inability to retain potassium even during hyperkinesias.

Potassium deficiency is hard to measure; however in multiple studies with over thousands of athletes research has shown that athletes have a frequent problem of low potassium intake.

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