An aerobic engine is an aerobic engine no matter how it was developed. See Mr Armstrong as evidence...
__________________________________
Actualy Mr. Armstrong is about to provide us very good evidence to the contrary. From what I've heard, he is really strugling with the run training.
Think of it this way. Your body is a car with an engine, a fuel pump, and a supercharger (muscles, heart, lungs). You can spend a lifetime building a top of the line fuel pump and supercharger on your corvette. However, move them onto a Ford Focus and....well.......you are going to have the fastest for Focus in town, but you won't compete against a Mustang. You still need to build the engine.
In other words, yes, the strong heart and lungs will help, but they are less than half the equation. You NEED to build mitocondria and capilaries to the specific muscles that are used.
Again, even if it doesn't "make sense" note that not one single elite runner does any significant amount of cross training.
-----------------------------Baron Von Speedypants
-----------------------------RunTraining articles here:
http://forum.slowtwitch.com/...runtraining;#1612485