He traveling with me needs the best blood, thews, endurance
— Walt Whitman, Song of the Open Road
As someone who loves to explore forest trails, I nonetheless spend a fair amount of time at the local track. I’m always trying to run a little bit faster, and I love to make progress.
One of my favorite track workouts is called the Yasso 800. It consists of ten 800-meter (or 1/2 mile) intervals, with 400-meter (1/4 mile) jogs for recovery in between. The name was coined by Runners World editor Amby Burfoot in an 1994 article after he heard his colleague Bart Yasso claim that the drill would predict his marathon time. It’s simple, Bart explained: the average time for the 800-meter intervals in minutes and seconds would predict his marathon time in hours and minutes. For example, an average interval time of 2 minutes 50 seconds would correspond to a marathon finishing time of 2 hours and 50 minutes. The relationship could be thrown off by heat, wind, or hills, but the intervals had proven a reliable indicator, at least in Bart’s own experience.