I totally agree w/ the article, that it's best to exercise later in the day. On weekends, I don't mind 9:00 or 10:00 but really the late afternoon runs after work, I'm sort of *charged up* and have some steam to blow off and a lot of my best runs are then? I had a really nice Turkey Trot on Thanksgiving but skipped eating the night before (cf. Jeff Galloway's books...) and had sort of focused training, intervals, etc. beforehand? I felt the 'flow' sensation I get into more than some of the other races I've run where it took 2 or 3 miles to wake up/ warm up? At 3:30 or 4:00 PM, I don't have to worry about waking up at all, it's just maybe 1/2 mile to warm up and I'm good to go however far I'm going? A lot of times, when I run then, I am planning say 5 miles but will run a couple more once I get going because I feel better, it's smooth, getting across the busy street works out easier than I thought it would, etc. I'm not sure that this has all that much to do w/ diabetes either? One of my buddies likes running in the AM but most of the time, if I run in the AM, it is much less comfortable and can be downright unpleasant. I think that it might be better, in terms of fat burning and hitting the right point in your 'metabolic curve'?
I sort of suspect that "Dawn Phenomenon" would be an evolutionary response to hunting and gathering, in that Neolithic's bodies would crank themselves up to go find grubs and berries to eat? I can't think of any other reason you'd want your BG to go up in the AM?
Plus, exercising without any insulin 'on board' is, for T1, a huge advantage. I had one good race I actually bolused a reduced bolus during the race because of some blunders beforehand but, most of the time, I prefer to empty the insulin out to have a better run.