Effectiveness is doing the things that get you closer to your goals. Efficiency is performing a given task (whether important or not) in the most economical manner possible. Being efficient without regard to effectiveness is the default mode of the universe.
Tim FerrissThere are a lot of things that can be learned from the darker corners of athletics. You have doctors who view bodybuilders as cavalier amateurs of science. And then you have the bodybuilders who view the doctors as too conservative to do anything interesting. So I've tried to become the middleman for putting some of those pieces together.
Tim Ferriss