Legs were a little tired, and I hope to do a longish ride this weekend, so I decided to play a game with myself, and ride with as little effort in the lowest gear possible, always keeping a high cadence with minimal effort. Told myself I was shooting for my record slowest commute time. Over a half hour commute, I was only about 3 minutes slower than my normal 'moderate pace' approach, and maybe 5-6 minutes slower than when I'm feeling gung-ho.