If you think about the cramp remedy that you see on a sports field, it gives us a big clue that this does not have much to do with salt. When we feel that agonising pain, the best evidence suggests that it is stretching out the muscle, not fluids, that provides relief. If you feel that pain in your calf muscle you grasp your toes and gently ease your foot towards you. This stretches the muscle and eventually eases the pain. No increase in sodium levels, by whatever means, are needed.
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