Aerobic energy and % of fat and energy used...

[rehab]

Is it true that you will only burn fat during aerobic excersise if your glucose levels are depleted.
So the general knowledge that doing excersise between 60% and 80% of max heart rate maximizes fat burning is a myth...
PLease help a guy burn his love handles off. (the natural, no juice way...)

[LM1332]

yea during the excercise only glucose burns and only after that it will start to burn fat. So the deal is just do cardio and dont consume alot of sugar but consume fructose(sugar from fruits or honey)

[BrokenBricks]

No the glucose bofre fat thing is a myth....maybe during high intensity cario for 10 minutes you could make a case for it but otherwise no. An informal proof of this is people who do no cardio but lose weight slowly over a year by cutting out their daily dougnut. Do you think these peoples glycogen yo-yos from 0-100% each day? By the logic above their glucose would have to bottom out to lose any wegiht at all. The body is going to do its best to keep a supply of glycogen stable. Its just a question of response time. Fat takes longer to mobilize. If your doing cardio so intense that your fat release cannot keep up you will burn all of your glycogen....But in general most people workout at a rate which temporarily lowers glycogen to some % of its original value and lipolysis winds up kicking in with enough force to prevent further depletion. What important is not glycogen loss, but muscle loss. Work at a rate beyond your bodies ability to mobilize fat for longer than your glycogen can last and you have protien breakdown.