I read that biking 5 miles in 30 minutes is a great cardio workout. The article said that 4 miles in 15 minutes would be just as great a workout. So this morning after Del went to school, Julie and I followed the 20 min Pilates DVD as a warm up (because I was a tad stiff this morning after yesterday's activities) and then I used our recumbent bike to pedal 4 miles in 15 min.
I had set the time for 30 minutes, but after 15 I was ready for an end. I think that is another "work up to it" goal. Just the same, the nice thing about the recumbent bike, other than low impact, is the read-out of statistics. My heart was in the THR and I did burn off my yogurt and blueberries from breakfast. Of course, this left me famished about an hour later so we've already had our leftover split pea soup and bread (w/mozzarella cheese).
Without burning out for my potential off day, I am looking for MORE to do, now.
Also, it occurs to me that my schedule is tentative and more of a suggestion than a rule.... So far it is working out!
ETA: I biked 15 miles after that first 15 minute attempt. I am still working up to 30 minutes, but by then I want 8 miles!