Excellent question... I would imagine that answers to this would vary, dependent upon a persons state of health and mineral balance.
I have had night leg cramp, restless leg, and muscle spasm issues in the past that have all but vanished since moving away from doctors and focusing on my wellness. When I focused my diet more towards mineral consumption than vitamin I saw the greatest improvement.
I did, have a few interesting foot issues like yours one night after starting the BSM/LJ/PL/ES drink, but continued and have not had that happen since.
My body was definately doing/telling me something though.