I surely do not tolerate the heat/humidity as well as when young. I get my miles in early morning. Today, here on Delmarva, the temps are reading between 96 and 100 the last couple of hours. In the summer, for the past 3 years I drove an open air trolley for the town Bethany Beach. No ac and in the beating down sun for 7 hours and that has lot to do with my quitting that job. I know the drivers are miserable today.