What causes muscle cramps?

[pompste]

I exhausted my body with a 2 hour body building workout today and now i`ve got painfull muscle cramps in my forearms and calves.I`ll massage them out as i`ve always done before----but it got me wondering as to what the real cause of the muscle cramps are.
Any information will be appeciated.

 

[msam76]

Increase water intake.

 

[msam76]

http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=270&topcategory=Sports

 

[LOL72]

drink more water.....also a lack of potassium soo eat a few bananas a day