For cramps try high dose of calcium 1000 -1200 mg as you feel cramps coming on. In high heat I have cramping issues at the 75 -100 km point. I've tried everything to date, pickle juice, tums etc. It is not an electrolyte or hydration issue for me. My sports Dr. said try the calcium and it has worked wonders for me. I get the soft chew 600mg and take two at any sign of cramping and have not had cramps since.