Is It True?

chikster · 15-Jul-04, 08:00 PM

Hi Guys! I heard recently that perrforming an exercise a little bit slower for a longer period of time will burn fat - not carbohydrate. Although when switching to anaerobic exercise it burns carbohydrate only. It seems weird? Performing an exercise easier and yet still burning fat.. Is it true?

trHawT · 16-Jul-04, 06:25 AM

When I do cardio, I try to do it first thing in the morning. Usually, the body is carb depleted, in which the only fuel source to burn is fat. Protein will be spared if you consume enough. I think your body is more likely to burn Carbs first, fat second, protein last?!?!?!?! Some of the posts on DF, about protein intake, are a little much.

**Firehawk** · 16-Jul-04, 06:39 AM

I think you have it backwards chikster.

For instance, Hi intensity interval cardio will burn glycogen (energy in your muscles) first, and then your body will burn fat after you are done with your cardio session to replace that glycogen. Lately the word is that HIIT cardio is much much better for burning fat while trying to maintain lean body mass.

Low intensity (endurance) cardio will burn fat during the exercise, but doesn't burn anything afterward, and you run the risk of losing muscle mass as well, which in my opinion, should never be the goal of ANYONE, but some people tend to disagree with me there lol.

chikster · 16-Jul-04, 08:18 PM

yeah, that seems to make some sense now because im trying to build lean muscle mass and get rid of fat! its just alot harder for women i believe to get rid of the fat in the places they want to! grrrrrr!

:

nate · 17-Jul-04, 12:16 PM

the fat you want to get rid off will be the last to go.

smm3 · 23-Jul-04, 02:47 PM

Quote:

Originally Posted by trHawT

When I do cardio, I try to do it first thing in the morning. Usually, the body is carb depleted, in which the only fuel source to burn is fat.

Actually, the first thing that you will burn is glycogen, if you haven't eaten anything then your body will pull its stores from the muscle!! You should eat a little something before any exercise. That will induce the body to do work-digestion-and thus increase your metabolism. This will also prevent you from losing any muscle that you have worked so hard to obtain.

The body, in a "starvation" mode since you haven't eaten in probably 8-10 hrs because of sleep, will save fat for last. It doesn't know when it will eat again, so fat is needed for long term energy, insulation, and protection for the organs. Muscle doesn't play that big of a role in survival.

Axion · 26-Jul-04, 09:50 PM

I too have read that lower intensity cardio causes your body to run on more long term energy stores...ie fat. High intensity cardio burns sugar stores first.

Firehawk....would you mind explain the reason why lower intensity cardio can cause musscle loss, because this doesn't make intuitive sense to me.

chikster · 26-Jul-04, 11:58 PM

Yeah, this is getting really really confusing :confused: Someones says its lower intensity cardio that burns fat (which i have read) and then someone else says that HIIT is the way to go to burn fat stores. Does anyone REALLY know which is correct, because from what I have read, the lower intensity cardio - burning fat makes sense. I'll try to find the article in which I found the info.

smm3 · 27-Jul-04, 05:52 PM

Okay, chikster, if you want scientific, here it is...

It is true, when you work out at a lower intensity, a higher percentage of your calories burned are from fat. However, when you work out at a higher intensity, you burn more calories overall.

(I am trying to make this as simple as possible.)

Let's say you walk on the treadmill for 30 min and burn ~200kCal, about 120kCal are from fat. If you work out the same amount of time at a higher intesity you will burn ~400kCal, about 140 from fat.

So you can do your lower intensity workouts, just for longer periods of time.
And just to make sure, do know what your Target Heart Rate is for your cardio??

chikster · 27-Jul-04, 06:11 PM

Yes, I wear a heart rate monitor when I do cardio... My target heart rate is 125-135.

Axion · 27-Jul-04, 09:13 PM

Hey Smm3....do you know the answer to why lower intensity cardio could lead to musscle loss, as firehawk was saying? I'd really like to here the thinking behind that theory.

smm3 · 27-Jul-04, 10:56 PM

I think what he was referring to (purposely or not) was the fact that the human body will adapt to whatever stresses you put upon it. And what I mean is that the body wants to be efficient, to use as little energy as possible, kind of a survival of the fittest thing.

You know that when you train, you must adjust your program due to strength gains. Along the same lines, when you do cardio, your body will adapt. If you train by doing long bouts of cardio, your body will become streamlined and more aerodynamic to facilitate that activity. This is because eventually the energy source runs out and the body uses the extra muscle for energy. Have you ever seen a marathoner or a cyclist like Lance Armstrong. They have very little muscle mass, but can run or bike for hours.

Cardio training is meant to optimize the body's ability to deliver oxygen to the muscle. When training this system properly, the effects last long after you have gotten off of the treadmill. The muscle is where you burn calories, if your goal is muscle building, strength gain, or fat loss, then (depending on your fitness level) interval training is definitely the way to go.