I look forward to holidays, as that is the only time when work doesn't get in the way of training. I tell the family that it's my time too.
I did some great training every day in Jamaica in 09, big bad hills that I had to do twice to get the distance (and avoid the dogs). Temps were 25-28 at about 0700. A second session on the hotel tready when it was hotter. That was 50 and 60 mile weeks, but no more than 10 at any time. I did great PBs afterwards.
Last month we were in Rhodes, where the temp climbed to 38 by mid afternoon. In those temps 45 minutes was enough. I tried the morning, which was much better but not exactly cool. You have to accept that it's going to be sweaty, and that you'll need to replace fluid AND SALTS.
I always use dioralyte or Boots own version. It's sold to help rehydrate if you've got the trots, and it's the right stuff and easier to transport than sports drink powders.
I'll even do long runs in the heat if I'm mid way through marathon training. 3 hours in 25 degrees plus. The difficulty I have with those is navigation. A Garmin 305 was a real bonus. I could tell you the story about the run near Lake Garda that was supposed to be 8 miles but took me over 3 hours due to navigational challenges and dehydration. I must have done nearer 20 miles in 25/30 degree afternoon sun. Memorable.
