I have been thinking a lot about magnesium (Mg) lately. Not because I am a geeky scientist (I have a PhD in Chemistry), but because I have been experiencing foot and calf cramps during and after training sessions. Two things happened that led me to magnesium. As Beth my Crew Chief often does, she struck up conversation with a lady that looked like an athlete in the grocery store check-out line. Turns out the lady is a serious runner. Beth mentioned my calf problems and the lady immediately said I should be taking a Mg supplement because I train in the hot Texas summer. The second Mg clue I got was at Ironman Vineman last July. As I was going through my “swag” bag, I found a little packet from MgSport® containing magnesium capsules to prevent leg cramps. I thought I should do some research.