Started at temp 73, DP 71, ended at temp 80, DP 72. Ran from Fletchers to Pierce Mill and back, with Jessica Chin for most of the run. Was struggling with the humidity for the most part, and probably shouldn't have picked it up on the way back. Ended up taking two breaks to catch breath when my chest was getting tight - one in Georgetown by water fountain; the other about a mile from Fletchers. Really hated to do the second, but I was in trouble - very characteristic breathing through a straw feeling.