Provided there are no neurological causes, you should try adding some extra calcium to your diet. Any good calcium supplement. If you can also get a Calcium, Magnesium and zinc combination as well. Also try drinking more water throughout the day as well. Also as the beginning of the day, do leg stretches along with in the evening as well. Try this for a week or two, if it doesn't improve then you should see your doctor. Generally those that are on their feet a lot and get the spasm Calcium usually takes this away.
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