Quote Originally Posted by christopher leigh View Post
Oh I agree in terms of energy, but not in terms of movement. Anyone who shuffles hours on end would naturally be more economical in terms of energy than a 4minute miler, because the pace is slow and when you're constantly draining the energy from your body it will rebel. The only way it can do that is to force the athlete to a speed equal to a shuffle.
You're bouncing all over the place here CL... I never mentioned movement when talking about economy, it was you who made that leap, I was referring to utilisation of fuel types. This is easily measured by gas analysis on a sub-maximal treadmill test and shows the point, relative to exertion, where the athlete is no longer able to use fat as a fuel and carbohydrate metabolism takes over completely. Take an ultra-runner and, because of the disciplined long slow distance work they've done, they will be able to maintain a degree of fat metabolism at a much higher level. This has obvious implications for distance running as you can only assimilate a relatively small amount of carbohydrate on the go so, unless you can tap those fat reserves, you'll come to a grinding halt. Distance runners develop their ability to utilise fat with long steady base work. It's essential to their performance so isn't junk.