Running in the heat Clip of the “Vestingloop” in Den Bosch on a pretty warm day. walking and running wearing different shoes on a tredmill. This clip shows how hot asphalt can get on a sunny day. It was about 35 degrees airtemperature, asphalt can get around 50. At the end of the clip you can see the significant cooling effect of trees. Might be relevant when organising a run on a hot day.