Jog for 20 minutes in your local park.

“Several days later, I drove to a small park where I had often seen joggers. The path went in for about a mile and a half to a dead end. You had to turn around and come back out the same way. My plan was to run on the way in, then cool down by walking back. The park was more crowded than I’d remembered: mothers with strollers, couples walking hand in hand, people with dogs, and, worst of all, other (better) runners. I paced back and forth by the entrance for several minutes — “warming up,” I called it, though I knew better. Finally I plunged in, happily dashing past mothers and couples and dog-walkers. All was well, for about nine minutes, which didn’t even bring me close to the end of the path. Hunched over, hands on knees, my face a fiery red, I realized that I would have to trudge back, encountering all those people I had passed just moments before. As I made my walk of shame, they would gawk, aware that I couldn’t even run a mile.”

“It was during this period that I took the big step off the running machine and into the outside. I went for "a run" in the park. The first thing I noticed was how much faster the time went by outside. Ducks, swans, leaves, dog shit, pedestrians, people on roller blades, other joggers (how quickly they all went); a world of amusement to keep my mind from my watch. Within a month I was going for 20-minute runs. About 30 minutes door to door, with walking at each end. No equipment, no fuss and bother getting to a gym. No faffing about.”