In some people, the calf and other leg muscles go into spasm while they are sleeping — causing them to wake during the night. Though it may help (though painful) to walk the cramps off, they disrupt sleep and prevention is a better answer.
Nutritional deficiencies, tight calf muscles or cold feet can all contribute to night time leg cramps.
Therapies & Advice
Stretch your calf muscles before you go to sleep. This can be done by pulling your toes towards you when you’re sitting on your bed.
Keep your feet warm
Wearing socks at night can also help because cold feet will sometimes be a trigger.
"Odd" bar of soap trick
Interestingly, several readers of Dr. Peter Gott’s medical column have noted that leaving a bar of soap under their bed sheet stopped their leg cramps. It seems odd, but it is cheap, safe, and easy to try — and has been working for folks! (I have no idea why it works.)
Supplement with potassium. This can be done by prescription or by eating a banana and/or drinking 12-16 oz (360-480 cc) of V8® or tomato juice daily.
Take calcium 500 mg at bedtime. It must contain magnesium and vitamin D in the calcium tablet.
Take magnesium 200 mg plus B complex (or simply add a multi-nutrient powder for overall nutritional support).
Although the FDA recommends against its use, taking a Quinine tablet 200-300 mg before bedtime can help in severe and refractory cases.