I tried today running 2.5 miles following Jeff Galloway's suggestion of using a 30:30 (seconds) cycle of running and walking. I ran for 45 steps with my left foot and walked for 33 steps. Later, as I started to get tired, I still ran for 45 steps and walked slower for 30 steps. To make it easier to monitor the time, I started when the "second" digits were 0 and changed to walking when the digits were 30. Sometimes I would run or walk a little bit more than I had planned, and I would compensate by decreasing the number of steps walking. Although, towards the end I was getting tired, and I compensated by decreasing the number of steps running. I'm hoping that after doing this a number of times, it will become automatic and I'll be able to "feel" that it is time to change. The number 30 likely isn't a magic number, and if one does short spurts of running and walking, the benefits will probably accrue.
Did I go faster? I don't know since I didn't have my Garmin with me, but it did feel like I was going faster. My body-energy was spread over the whole run, and that contributes to a faster speed. I noticed that the limiting factor was my body rather than my legs. It's been a number of months since my body limited my running. Due to a busy schedule today, I only had a dish of Corn Checks and a banana for breakfast at 8:30 am and no lunch or snacks. I grabbed a handful of Corn Checks before I left for running about 3 pm, and I ate an energy bar while driving to the Jordan River. So, my lack of good food may have been why my body was the limiting factor. My legs felt pretty good, thanks to the short spurts of running instead of running until my legs got tired.
All of this reminds me of my time as a Boy Scout. On of the requirements was to run the "scout mile" in 12 minutes. The scout mile consisted of alternating 100 steps of running and 100 steps of walking. The scout mile was not far off from what I did today.