So I thought an update was due. I fought through the demotivation and ran anyway. I took all the advice and repeated Day 1 over and over, allowing myself to walk during most of the day's 8 runs.
And when I did walk through a one-minute jog, I chose to see it not as a failure but as part of the process. Each jog was a success, whether or not I could do many of them.
My first Day 1: Barely survived 3 of 8 runs.
Nearly three weeks later: For the first time I actually jogged for all 8 one-minute runs of the Day 1 session. It was messy. I was out of breath. But I did it.
Happy running to all y'all.
