Ha, so true, and in fact I did try thinking about it, and the thought that came to me during my attempt is that hills might be the solution to my current malady--a stubbed toe that's taking forever to lose its tenderness. So I've run hills three times over the last seven days. And it works! Less impact--because of the reduced angle and slow pace--but plenty of aerobic conditioning, so that, when I can finally run at a decent pace on flat ground without aggravating my left big toe met head, hopefully I won't have to stop every few steps to catch my breath. Or maybe I'll just stick to hill-efficiency, and give up the running=mileage concept, to more of a running=conditioning concept.
Maybe we've coined a neologism: running intentions = "runtentions." Or, more generally, "excertentions." What are the intentions driving our flexions, extensions, and mended mid-sections?