>Also, how do you figure your in the "zone" for maximum weight lost? What is
>the pulse you should be reading? 10 beats? 20 beats?
I'll take a stab at it fresh, and maybe Rick can correct me if I'm wrong ;-)
First, the physiology of running dictates that two substances will be used
as fuel during exercise. One is a sugary-based substance like glucose
the other fat based, as in fatty acid.
The "zone" is where the ratio of fatty to glucose based fuel consumption favors
the former. When you begin exercise you burn relatively more glucose
and the longer you go, the more fatty fuel you burn relative to glucose. This
change occurs somewhere between 40-50 minutes.
So, first, you should set a goal of exercising ~1 hour.
Then, to truly understand weight loss, you must realize it is a function of caloric
intake vs expenditure. So, the higher you perform (as measured in MHR
for example) for that hour, the more calories you'll burn and the more
relative fat you'll consume. Target ~75% of MHR.
But as Rick has pointed out, the net amount of fat consumed during this
time is marginal at best. So, for truly long-term weight loss the rest of the
day is equally important as the hour of exercise. Only by combining the
long run with sensible diet are you assured to meet or exceed your weight
In practice, this has been my experience. I've also had good luck
with "The Zone" diet during this time...But that's another story all together.