80% Engine

+sitting back with some popcorn and a beer to watch the show+

That's correct! I know it sounds low, but if you are trying to teach your body to burn only fat as fuel and not carbs, you need to start out in the lower 10 %. After you have gotten it used to using fat calories, you can then increase your heart rate gradually. You will learn to feel the difference when you switch from fat to carbs. Even with carb loading (eating high carb meals prior to a race) that fuel is minimal and will wear out quickly. It's like 2 drivers are driving in a city. One makes rackrabbit starts, accelerates to each stop, then brakes hard at the light. The second driver starts normally, accelerates slowly, then stop sensibly. Burning carbs, unless you are trying to build muscle, will not give you a lot of success at burning fat. I know it sounds backward, it seems the harder the workout, the more fat loss, but it doesn't work that way. Only thing I can say is to try it and see if it works for you. I've lost 65 lbs in about 6 months. I do 10 workout a week (AM every day and PM M,W,F) and I've never felt better.

Alright! First a little background. As a person ages, their TZ or target zone will change. The way to calculate your own personal TZ is to subtract your age from 220. You then multiply 60% by that number. That is the low end of your target zone. Take the same number and multiply it times 80%. That is the high end of your TZ. If you are in really good shape, you can go to 65% and 85%.
Here is an example:
220 - 56 (my age) = 164
164 X .60 = 98 (my low TZ)
164 X .80 = 131 (my high TZ)
The TZ applies to your heartbeat
Now there are three types of exercise: Aerobic, Anabolic, and Canabolic
You guys can look up detailed explanations if you wish.
Briefly, they are:
Canabolic - The body actually starts to destroy muscle mass.
Anabolic - This is the phase that actually builds muscle
Aerobic - This is the phase that tones muscle and the one we will be concerned about.
Have you every noticed that you get that muscle burn if you start to push things? That is lactate acid build-up and means that your aerobic exercise has now become Anabolic, and you have stopped burning fat. If you are weight training you want that Anabolic burn to build muscle. Not to burn fat.
The way to use the 80% engine is to exercise in the bottom 10% range of your lower target zone. This does not allow the body to burn carbs, it will only burn fat. Lance Armstrong made this tactic popular several years ago. He called his fat "engine" his 80% engine and the carb engine his 20%. The neat thing about burning fat is that when you start doing this you will have much more stamina. The carb engine can be used for sprints, hills, etc.. As a weight loss tactic, the 80% engine works well for loosing the unwanted pounds and inches. As you start to do this, you may find it hard to keep your heartbeat down into the lower 10% of your TZ. Give it a try!