[Scott Johnston]

Matze:

I undertsand your question but I would like to correct one thing before we move on to answering what you asked about.

Unless your interest is in losing fat the main goal of aerobic base training is to be able to move faster at your aerobic threshold.  I think most athoetes will have improved performance as their primary goal and the increased fat metabolism will be a follow on effect.

FATmax does not always coorespond to AeT.  In my experience those two events tend to coinside in very well endurance trained athletes.

If these two points are far apart and your goal is to improve your fat useage you will need to train close to your FATmax.  In that same athlete if on the otherhand you want to improve your speed at AeT you will need to train closer to AeT speed/HR.

I hope this helps.
Scott