Maffetone is the slower is better training by using a heart rate monitor. 180 - age with a + or - depending upon your fitness level. I haven't tried it, but I am skeptical.

Has anyone here done this method, and have data to back it up?

It seems to me that as I would run more, that my heart rate would be a little lower as I improved at the same pace, which is basically the same thing, but he is saying to run at a heart rate instead of a pace.

So, if I would jog at a heart rate of 135 continuously, I would start getting faster pace times, and hopefully increase the distances also.