For my second week of riding I upped the anti. I added a lap around the block which happens to be 4 miles with hills. Much harder work to get up those hills than the flat I was already doing. The plus though is that I get to go downhill fast. The hills are not steep enough to meet the speed limit, but it definitely makes the ride more fun. It also makes me want to fall asleep sooner. I can concentrate a lot better after a ride, so I should probably plan to ride early in my day.