another question

[robert13]

Thanks alot for answering all my questions you guy's are great. Well i wanted to know since i'm a kid i want and to hold on to all my muscel right if i want to grow into a strong man right, so the question is when does your body start eating muscel i know when you lift for more then 45 min, and in the morning if you don't eat anying and how about cardio like running if you run for more then 45 min will i start burning mucsel so please help thanks.

p.s i stoped lifting to dangerus right now all i do is body wight exercise's to stay in shape.

 

[Fil]

Here are some basics:

Your body has three primary energy systems - in order of how your body uses them:

1. Phosphagen system - runs off carbs. Used at the beginning of every exercise, no matter how intense.

2. Glycolysis - runs off carbs. Highest-output energy system. Used for first 20 minutes of intense workouts.

3. Oxidative System - runs off fat, and to a much lesser extent, protein. Low output energy system. Used during low-intensity exercise, day-to-day tasks, and a last-ditch effort if other energy systems fail.

So when you exercise this is how your body does it:
Start of exercise - 30 secs : phosphagen system
31 secs - 30 minutes : glycolysis
30+ minutes : oxidative system

Now Note: Each of these systems is generally ALWAYS in use, but which one is used primarily depends on the availability of nutrients essential for that system, and the intensity of the exercise in question.

High intensity exercise REQUIRES the Glycolysis system because it produces energy faster than energy other system.

Low intensity exercise utilizes the Oxidative system because fat has a high energy output, but can only be liberated VERY SLOWLY.

So in long-endurance exercises, what happens is your body burns through your carbs in supporting the oxidative system, and in order to continue producing enough energy to continue, it has to break down your muscle protein in order to supplement the slow-to-release fat energy.