I race in Florida during the summer. There probably isn't a hotter place on earth then the Sebring Long Course ECR in late Aug. I sit on a 10"x10" gel filled pac I got a few years ago when I hurt my arm. Keep it frozen and it lasts about 20 minutes. Also use the ole ice in the glad bag trick and support it with my ample shelf inside the uni. I already know it's going to be hot, so it's really not a factor when you live with it. Mistake I have made is not hydrating enough BEFORE the weekend. You have to double or triple your fluid intake way before the race, not right before or during.