Hill repeats

My neighbor's kids must think I'm nuts now, because yesterday evening as they were racing their bikes down their driveway, I was running up and down the steep hill on the road in front of their house - over and over again. I decided to add hill workouts back into my training, and yesterday was my first plunge back into it.
I warmed up with a slow half-mile on the treadmill, stretched, and then did a steady mile on the treadmill at about 6-6.5 mph before going outside to do the hill repeats. My goal was 5 minutes of up-hill running and to jog down instead of walking. It went pretty well, considering I was tired (don't know why, since I had a full day of rest on Wednesday). I thought about quitting after 2 and a half minutes, but I told myself that this was a hard workout and it was supposed to feel hard, so I should just do it. (I guess I'm becoming a Nike spokesman now?) It took roughly 45 seconds to run up the hill each time, and I had enough breath to jog down again, all except one time, which is a big improvement over my past hill workouts. When I got inside, I finished up with a half-mile cool-down on the treadmill and have been feeling good ever since. Today is supposed to be full rest, but I might take the Trek out to the trail for a bit.