It turned out there was a bunch of little kids walk-running around the school track. Harrumph. And here I'm a taxpayer and they're not. . . . (actually I found out later that it was Catherine and Elisabeth's class - but I didn't get close enough to see that!)
So I went out on the roads and just ran hard for 100 strides and then jogged until my eyes stopped bleeding, then repeated. Then that was too hard so I walked between sets until my eyes stopped bleeding. And then finally the intervals got farther and farther apart and then toward the end my eyes just wouldn't stop bleeding at all, so I crawled home.
Intervals are hard. And yeah, if you count the peaks, there are only 9 of them. I know, I know.