Does body fat % affect calories burned??

MissMe2morrow

I keep seeing all this information stating that it takes more calories to keep up muscle rather than fat. The thing is, every piece of gym equipment, and even my heart rate monitor, only seems to take into account my height, weight, age, and heart rate when calculating how many calories I am burning. Shouldn't that calculation include my body fat percentage as well? It seems like as I lower my body fat percentage I should be burning more calories. Can someone please help me understand this?

Ding724

*bump* I am very interested in the answers/responses to this!

Angel1066

So am i

angel_eyes17

bump - me too.

mnishi

Good question, I'd like to know the answer myself...

4theking

The whole muscle burns more than fat is highly overstated and amounts to next to nothing. If I remember correctly it is like 6 calories per lb.

bmontgomery87

I'm kinda confused on this one too.

I think muscle takes more cals to maintain. but .......hmmmmmmmm.

SaraTonin

Your lean muscle mass burns more calories than fat when resting.

When exercising, if you weigh more (have more fat OR lots of muscle), you will burn more calories because you have more "resistance." If that makes sense at all. This is calculated using a combo of your heart rate and weight.

When you think about it, the more in shape you are, the less "work" you have to do to run the same distances as when you were out of shape. Your muscles are already there and ready to spring to action for you!

rmhand

true that muscle burns more fat/calories but remember that you are losing weight and therefore not working as hard to move your body.
Less body to move = less energy(calories) to move it.

Akaratel

I agree with him above - I don't think it would amount to much, I found this...

Muscle Metabolism
The Mayo Clinic asserts that resting metabolic rates are higher in people with more lean body mass, or muscle. Claims have been made that muscle burns fat at rates upwards of 30 times that of fat. However, this appears to not be the case. Fitness author Christian Finn writes that for every pound of muscle you have, your body will burn about 6 calories per day. This is referred to as the daily metabolic rate.

Fat Metabolism
Fat metabolism, or lipolysis, has a daily metabolic rate of about two calories, according to Finn. Therefore muscle has a daily metabolic rate of about three times that of fat. This isn't quite as high as previous claims, however it is still a valid reason to build more muscle and decrease fat.



Read more: http://www.livestrong.com/article/256919-how-many-calories-does-muscle-burn-compared-to-fat/#ixzz1JQSlezCU

srp2011

Body fat % affects the calories burned when you are at rest, so more body fat = lower BMR, and more muscle mass = increased BMR. The amount that it would impact your workout routine would be trivial, so that's why it isn't incorporated in exercise calorie calculations. Like 4theking said, the whole thing is somewhat overrated - it does help to increase your BMR, muscle is more metabolically active than fat, but the absolute amount per pound of muuscle for fat is small, so unless you are seriously muscled, it's not going to have a dramatic impact on what you can eat to maintain your weight (and if you have that much muscle, you have to be working out pretty seriously, and that is what is really going to increase the number of calories you're burning each day, not the BMR). So it is much better to have more muscle than fat, but it won't give you the carte blanche to eat what you want, which is the mistake a lot of people make.

MissMe2morrow

I guess the age thing doesn't make much sense to me, either (sorry if I'm being dense-- I just really want to understand!). :huh:

The "target heart rate" to burn fat appears to be completely age-related rather than fitness related...

MissMe2morrow

Thanks everyone who has posted-- I am really glad to know that the calories burned by muscle vs fat is very minimal-- that explains a lot!!

hikingmonk

Here's a pretty good article with formulas explaining some of this stuff. I learned a bit just reading it now.
http://www.shapefit.com/basal-metabolic-rate.html

Age, sex,and weight are used in conjunction with statistical tables to estimate a person's LBM (lean body mass). Most people don't know what their body fat/lean body mass numbers are, so they use formulas based on statistical tables to calculate that number.

If you look at the last formula, which asks for LBM, you'll see that age is no longer part of the equation.

If you had accurate body composition numbers (body fat/lean muscle mass), you could in theory determine a slightly more accurate BMR. I'd be curious to know how much more accurate that would be.

Mayor_West

I guess the age thing doesn't make much sense to me, either (sorry if I'm being dense-- I just really want to understand!). :huh:

The "target heart rate" to burn fat appears to be completely age-related rather than fitness related...

The reason it asks for your age is to determine the percentage of your max heart rate that you're working at. For example a 23 year old working out with an average HR of 150bpm will be working only 50% of their max HR. A 55 year old working at the same average HR will be working out at about 90% of their max HR. As far as the HRM on the machine is concerned, it has to use the age of the person to determine the level of effort when it comes to estimating calories burned, even if in most cases, that number is inaccurate.

MissMe2morrow

Thank you! I will play around with the equations on that site... and try to find a different way to calculate my target heart rate.

hikingmonk

Here's a link from the Polar website with two options for calculating target heart rate zones. The 2nd equation takes fitness into account in addition to age. I had thought my old (and sadly lost) Polar 610i had some function for determining heart rate zones based on some kind of resting heart rate (similar to the 2nd option in the link below). Maybe your HR watch has something?

http://www.polarusa.com/us-en/support/faqs?product=&category=General&documenttitle=How+to+calculate+target+heart+rate+zone?&document=/gip/PEUS1kb-public.nsf/web_cat/85256F470048B0BC852574FD00655BD8

SaraTonin

Also, your BMR lowers as you get older.