Along with two of my brothers, we raced a mountain bike event called The Traverse, a Warrior Society mtb race in the Cleveland National forest. 44 miles and 8,000 ft of climbing. Over 6 hrs for me and one of my brothers. A check point at 3/4 of the race, had a very large digital thermometer that read 106*. One of the people there said it earlier read 115*. I saw guys starting to cramp after the first 2 hrs. Not sure of the results yet, but my other brother did not finish due to the heat and took a bail out route. He said he saw 20 others bail out too. I will be interesting to see how many bailed.