Interval training. 5600 South, 1300 East, and Van Winkle form a right triangle of right-hand turns. We go hard on the hypotenuse and recover on the whatever the other two sides of a right triangle are called. It is self-directed but 4-6 laps over 40-75 minutes is kinda OK, if you need something to shoot at. Note, though, that I am making those numbers up.