Being the recipient, as I think we all are, of muscle cramps every once in a great while I started wondering about muscles that don’t seem to cramp; to wit: the tongue, the heart (I don’t think a heart-attack is a heart cramp, is it?), the muscles used in ejaculation and penis flexing, the sphincter muscles, stomach muscles (that is, the ones which actually manipulate the food in your body, not the six-pack muscles :p).
Is there a reason why these muscles don’t cramp up? Is there something to be learned here?
I can tell you for a fact that tongue muscles can and do cramp. Long sessions of oral sex performed on responsive (and usually quivering) women have proven this.
Basically, it’s a matter of smooth versus striated muscle. Striated muscle cramps, smooth muscle does not. Your non-cramping organs use smooth muscle.
I’ve cramped my tounge simply trying to get at a bit of food stuck between my molars. And the muscles involved in penis flexing and ejaculation can cramp - have sex half a dozen times in the course of a few hours and you may have some very interesting cramps the next day.