thank you, thank you, thank you!...Jan...yes I drink drink drink!...I prolly drink more than I should and on the days I mix all three events I drink an eletrolyte mix - but it may not be enough! I did take some extra calcium Wed night but both you N Trek made a wonderful point - I may be burning more than I'm replacing! (ok..that would be a duh but sometimes you need to get hit over the head with it!)......I'm going to try increasing actually 3 things - potassium, calcium and magnesium and I prolly need to start carrying the electrolyte mix in my water bottle. It only takes 1/2 hr to get home...but thats climbing all the way! Thanks so much for the "hit in the head"....I'll let you know how it works!