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Michael Draughon 04-08-2009 09:45 AM

when does fat loss start
So were doing sports physiology in class right now and talking about the different fuels your body is using to perform the said exercise. Correct me if im wrong on any thing but from about 10 seconds to about 180secs, it is mostly anaerobic and your energy is coming from glycogen, and mostly anything after four minutes is aerobic, but does not really start to use fat as a source of fuel, until perhaps twenty minutes of work. Most of crossfits workouts are are quick and intense and may not reach twenty minutes. So one, how do we burn fat with this style of exercise, and if our body needs those carbs, why do some Zone people after a certain amount of time reduce carb intake and increase there fats? I searched this out but did not find much. any info would be great

Jamie J. Skibicki 04-08-2009 10:05 AM

Re: when does fat loss start
It's not the fuel being burned during excersize, its the fuel being burned after the excerize.

Look at weight lifting. It makes you weaker. Recovering from it makes you stronger. There is more going on than what happens during the 20 minutes or so you are training.

Jenna Dodge 04-08-2009 10:24 AM

Re: when does fat loss start

Also...Think about when you get hungry...during a LSD run, for example, you will probably get hungry about 1-1.5 hrs into the run. After a typical short CrossFit metcon, you probably get hungry about 1 hr after the WOD, right?

Also, you do utilize fat as fuel during anaerobic's just a smaller percentage of energy than aerobic exercise.


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