After reading an article a few months ago about electrolyte depletion under intense exercise and the expected symptoms which were nearly identical with my own experience, I purchased SaltStick Capsules. Today was my first test in taking them in a 27.4 mile mountain trail race. For the first time I had no stomach cramping or muscle deadness at about 3.5 to 4 hours after race start nor at any point thereafter. I will always be taking these in any future races or training runs.