So I took the new shoes out for spin yesterday. For sure the problem were the shoes. I wanted to air things out a little to see how the new ones would feel. I comfortably put in four miles in 37 minutes. The only issue is that the foot beds in these GTs seem a little rougher than the Kayanos, so the soles of my heels started feeling hot toward the end of mile 3. The lurid details - 4 miles, 37.22 minutes, average heart rate 150. Not too bad for a slow old fart!
My only issue now is my hip. I had a fitful night of sleep because I just couldn't get comfortable. I did some searching on the Internet this morning, and my symptoms point to a hip strain. The research says that this can be caused by overpronation. My theory here (maybe it's something I want to believe) is that my old shoes were shot, allowing me to overpronate on my slow runs when I would be most relaxed. I guess I'll see here.
One thing that I am toying with is with the impending rain, maybe I'll take the week off after my 10K on Sunday. If it is a hip strain, the rest should resolve the issue. If it doesn't, then hello doc!