Don’t wait to take walk breaks. By alternating walking and running from the beginning, you speed recovery without losing any of the endurance effect of the long one.
Be sure to do the running portion slow enough at the beginning of every run (especially the long run) so that you’ll feel tired but strong at the end. The conservatism will allow you to recover faster.
Every other day you can cross-train instead of walking. Cross country ski machines, water running, cycling, and any other other mode which you find fun and interesting (but non-pounding) will improve overall fitness.
Stay conversational on all of your exercise sessions. This means that you should be exerting yourself at a low enough level that you could talk. It’s okay to take deep breaths between sentences, but you don’t want to “huff and puff” between every word.
As the runs get longer, be sure to keep your blood sugar boosted by eating an energy bar (or equivalent) about an hour before exercise.
