I try to ride 3-4 times a week. The rides are now up to 10-12 miles of mostly gravel, potholes and hills. I also am hiking some in-between, and I ride horses. I've found that switching things up is helping me stay active and at it, not getting bored. Just did a 12.5 mile mountain hike in just over 4 hours. I'm amazed at how fast both my lungs and my legs and my core are improving. Planning a 17 mile ride on a mildly hilly paved bike-path for tomorrow.