Amby Burfoot reports from the Chicago "Science & Medicine of the Marathon" conference:
"a number of different speakers circled around the topic of running economy. What they seemed to be saying, at the end of the day, was: "We don't know much about running economy, neither what determines it or how it can be changed." ..
I was a bit surprised by this. I would have expected several of the speakers to talk about plyometrics, power-training, speedwork, pace-training, and the like. But they didn't. Instead, if anything, there was a trend toward the speakers saying that more running, which means slow running, produces better economy."
http://rodale.typepad.com/footloose/

who knew ? hah !