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Singel
10-22-2004, 10:03 PM
So on the eliptical machines i use there's a little chart with ages, and heart rates for high intensity/low intensity fat burn work outs. Sometimes I'm way above, and sometimes I'm right on it:dunno: , but I don't know what the hell it means. Can someone simplify it for me? I always here you wanna get your heartrate in the target zone for fat burn, so if I'm above it should I speed up/slow down?

badseed
10-23-2004, 09:05 AM
The fatburn zone is misleading. Think of it this way - the more calories you burn the better, accomplished through duration and intensity. You don't actaully start utilizing your fat reserves until your carb reserves are depleted, as a general statement this takes approx. 30 minutes depending on intensity.

Marsh
10-23-2004, 09:42 AM
That Cardio zone thing on the eliptical is the zone thta you want to be training in if your all for endurance and stuff, but yeah otherwise the fat burn zone, but yeah like badseed said it doesn't really matter , as long as the calories are being burned

xrayvsn
10-23-2004, 02:43 PM
The cardio "zone" is supposed to be where you are still doing aerobic exercise. The body doesn't burn fat while anaerobic. You also can't exercise as long if you're anaerobic, though you do tend to burn more calories for each increment of time.

The best way to tell if you are still doing aerobic exercise, is to see if you can still hold a conversation while working out. If you are so short of breath you can't talk between breaths, you are definitely anaerobic.

In the end, its the total calories used that matters most in losing weight. You have to utilize more calories than you are taking in, simple math.

FiveFreshFish
10-23-2004, 02:48 PM
Originally posted by xrayvsn
The body doesn't burn fat while anaerobic.

What is the source of energy when you're in the anaerobic zone if it's not fat? :dunno:

^SkylinE^
10-23-2004, 02:55 PM
^^^^ food intake carbs

Singel
10-23-2004, 02:57 PM
So if I run for an hour so fast that I can't talk, I'll burn less fat, but burn more calories than if I run slowly for an hour?

xrayvsn
10-23-2004, 03:05 PM
Biochemically, if you're looking at it at a cellular level, anaerobic metabolism only utilizes glycolysis, which only metabolises glucose. Fatty acid metabolism needs oxidative phosphorylation to function.

"Fat is burned in the fire of carbohydrates"

It is not this simple when looking at exercise physiology, since you have limited carbohydrate stores (circulating glucose, glycogen in muscle and liver). Only few tissues can use fatty acids as a primary energy source (brain does), the rest need carbs to use fat.

All of this is not what is important. Basically, you want to raise your heart rate, and maintain that increased output. It doesn't matter where the calories are coming from, as long as they are expended. Let your physiology worry about glucose production/fatty acid metabolism.

Stratus_Power
10-23-2004, 03:12 PM
and remember it takes 3 times as much energy to break down one Fat molecular than to form one!

~Leah~
10-23-2004, 04:15 PM
Yeah, the "fat burning" zone on those things is really misleading. Like someone said, the more calories you burn the better. Your body uses energy in this order: carbs, fats, proteins. It does take approximately 30 mins to deplete your carb energy, then your body uses fat as a source of energy.

As well.. think of it more in an "effort exertion" standpoint. Were you working at your 80% maximum effort? (i.e. keeping your heartrate constantly at 80% maximum [approx. 220-age] effort) That's basically what that stuff means. The more exertion you use, the harder workout you had, the more energy your body utilized the more fat you potentially burned.

EDM
10-23-2004, 09:56 PM
Biochemically, if you're looking at it at a cellular level, anaerobic metabolism only utilizes glycolysis, which only metabolises glucose. Fatty acid metabolism needs oxidative phosphorylation to function.

sounds like u took bcem443? :D

xrayvsn
10-23-2004, 10:03 PM
Originally posted by EDM


sounds like u took bcem443? :D

About a decade ago. In another life, I was a BCEM major. Good to see that the curriculum hasn't changed.;)