persistent cramp

Hi,

Just wondering if anyone has any advice. I seem to be getting cramp in my calves and feet more frequently recently. It seems to come on at different times (sometimes when lying on the couch, often in bed in the morning and very often during my pilates classes) and while not severe is starting to get really annoying.

Does anyone have any suggestions on what could be causing it or how to stop it happening?

Any advice greatfully received!!