I can't quite get my head round this. Yesterday I rode 40 odd miles. It wasn't all that hot although the humidity was up a bit. Normally when I get home my wife has to peel off my sweat soaked kit from my body. Yesterday I was bone dry. No sign of sweat at all, and even whilst drinking a hot cup of tea my body remained dry. My urine was very dark. I didn't think of it at the time but I went for a pee when I got up about 7am, and didn't go again until about 3pm. During the ride I drank two 700ml bottles of water with a bit of fruit juice for flavouring. I remained in this state until I had dinner about 6:30pm, then I began to sweat, and within minutes I was soaked. Clearly I was dehydrated. My urine is still dark this morning but becoming more pale. If this is what normally happened I wouldn't be concerned. It is the fact that it is a completely abnormal reaction for me. I am sitting here now sweating and not even doing anything. That is normal for me because of medication I am on. I guess I am going to have to keep track of things for a while.