Muscle vs. Fat

joshuakcaron

So I read somewhere that muscle weighs more than fat. 1lb of muscle burns 6 calories to 1lb of fat.

So does that mean MFP estimates for calories could be significantly off if you are significantly more muscular than fat?

I ask this because I was only about 10lbs overweight according to my measurements and weight and people always guessed I weighed 50lbs less than I was. I used to be pretty athletic and I'm wondering if maybe I should increase the food I'm eating even more than I have if that might be the case.

Hope that's not confusing.

siluridae

1 lbs of muscle weighs exactly the same as 1 lbs of fat.
People are bad at correctly estimating weight. Most of the world is fat, people don't know what a healthy weight looks like. Muscle also doesn't stay around if you are not athletic anymore.
If you want to know how much bodyfat you have, go get a DEXA scan. It's not perfect, but it's the best you can do.

AnvilHead

Unless you're significantly more muscular than an average person of your height/weight/age (as in professional bodybuilder-type muscular), the difference in calorie burn is going to be so minor as to be insignificant.

A pro-level (drug-free) bodybuilder may have somewhere around 30-35 more pounds of muscle than Joe Average. Taking into consideration that a pound of muscle burns around 6 calories/day, that means his calorie burn would potentially be around 180-210 calories higher than Joe Average. Most people don't have anywhere near that amount of lean/muscle mass, so the burn would be correspondingly lower.

Although it's a pedantic and semantic point to make, muscle doesn't weigh more than fat. Muscle is more dense than fat, so a pound of muscle takes up less space than a pound of fat. One pound of muscle and one pound of fat weigh exactly the same - one pound.

Sued0nim

He clearly means 1lb of fat has more volume than 1lb of muscle, which is true

Does MFP overestimate calories for you? Stick to its limits for 6-8 weeks and let your body be the judge

It's all estimates what happens in your body is all that counts

Try not to kid yourself that what people say is anything more than the societal norm ...be objective

I carry weight well...but what counts is body fat % in physical appearance

blankiefinder

@rabbitjb and OP,

Since he's been averaging 6 pounds lost per week for the last 6 weeks, he can probably safely increase the amount he's eating

AnvilHead

blankiefinder wrote: »

@rabbitjb and OP,

Since he's been averaging 6 pounds lost per week for the last 6 weeks, he can probably safely increase the amount he's eating

If he's consistently dumping 6 pounds a week, a lot of that loss is muscle mass so he certainly doesn't have to worry about increasing calories to make up for his muscles!

Sued0nim

blankiefinder wrote: »

@rabbitjb and OP,

Since he's been averaging 6 pounds lost per week for the last 6 weeks, he can probably safely increase the amount he's eating

He's been what now?

Facepalm.gif

senecarr

On average a pound of muscle burns 6 calories a day while a pound of fat uses about 2 calories a day. That means that if TDEE calculations assumes a pound is body fat when it is muscle, it is probably off by 4 calories, on average.
Plugging that into the 30-35 possible range above gives 120 to 140, and that's for a very select, very elite level of athlete.

Of course, different methods of RMR calculation use lean body mass and fat mass differently.
For Katch-McArdle it will matter a lot because it uses only LBM to predict resting daily energy expenditure.

senecarr

The accurate way to know your RMR is to get it actually measured by oxygen expenditure.
The accurate ways to get TDEE are being in a metabolic chamber or doubly labeled water.

In practice, particularly for a lifetime where you can't afford doubly labeled water constantly in your system, you're going to have to just do as rabbit suggested and use your own weight loss as a feedback information for estimating your TDEE.

AnvilHead

rabbitjb wrote: »

blankiefinder wrote: »

@rabbitjb and OP,

Since he's been averaging 6 pounds lost per week for the last 6 weeks, he can probably safely increase the amount he's eating

He's been what now?

Facepalm.gif

As usual, we discover that context is very helpful in formulating an accurate answer.

joshuakcaron

AnvilHead wrote: »

Unless you're significantly more muscular than an average person of your height/weight/age (as in professional bodybuilder-type muscular), the difference in calorie burn is going to be so minor as to be insignificant.

A pro-level (drug-free) bodybuilder may have somewhere around 30-35 more pounds of muscle than Joe Average. Taking into consideration that a pound of muscle burns around 6 calories/day, that means his calorie burn would potentially be around 180-210 calories higher than Joe Average. Most people don't have anywhere near that amount of lean/muscle mass, so the burn would be correspondingly lower.

Although it's a pedantic and semantic point to make, muscle doesn't weigh more than fat. Muscle is more dense than fat, so a pound of muscle takes up less space than a pound of fat. One pound of muscle and one pound of fat weigh exactly the same - one pound.

Ah okay! I thought it was six calories an hour. Thanks for the clarification

AJ_G

rabbitjb wrote: »

He clearly means 1lb of fat has more volume than 1lb of muscle, which is true

True but overstated to say the least, 1.06 kg/L vs 0.91 kg/L, the actual difference in volume between two equal weights of fat and muscle is rather small. I've found that the whole "muscle weighs more than fat" line more times than not is just used as an excuse for those who aren't seeing their weight change on the scale and need to validate their effort

Sued0nim

AJ_G wrote: »

rabbitjb wrote: »

He clearly means 1lb of fat has more volume than 1lb of muscle, which is true

True but overstated to say the least, 1.06 kg/L vs 0.91 kg/L, the actual difference in volume between two equal weights of fat and muscle is rather small. I've found that the whole "muscle weighs more than fat" line more times than not is just used as an excuse for those who aren't seeing their weight change on the scale and need to validate their effort

Explain this then?

Sued0nim

That's interesting actually ...so there is less than an 18% difference in volume

All the images seem far greater visually ..must be due to muscle fibres holding it's shape whereas fat spreads

Although I suppose it's not to be considered in isolation on a plate ...physical appearance is remarkably different based on body composition

yarwell

I think the picture is a fake. For a start it looks like two types of plastic and how do we know the scales are genuine and not just disconnected with the pointers at the same place.

1.06 vs 0.91 is a relative volume of 1 : 1.16 not 1:2 or more as implied by the picture

Sued0nim

There are lots of pictures of fat vs muscle. I've seen them on scientific teaching supply sites and the proportions are always similar

I think it's one of this out of context visual propositions to make a point, particularly when considering the solidity of each physical structure

yarwell

rabbitjb wrote: »

There are lots of pictures of fat vs muscle. I've seen them on scientific teaching supply sites and the proportions are always similar

are any of them actual fat and muscle ? (before I start cutting up a pork chop and doing Archimedean experiments)

ETA: Someone cut up humans and concluded "For the six cadavers, whole body adipose tissue density ranged from 0.925-0.970 g/ml" http://www.ncbi.nlm.nih.gov/pubmed/8148928 .

AJ_G

rabbitjb wrote: »

There are lots of pictures of fat vs muscle. I've seen them on scientific teaching supply sites and the proportions are always similar

I think it's one of this out of context visual propositions to make a point, particularly when considering the solidity of each physical structure

Yea, all those pictures aren't actually using adipose tissue, and muscle tissue, they're just modelling representations and they're almost always inaccurate...

mccindy72

Having cooked with meat quite often, I can say that a 5-pound roast is not very large. Muscle is more dense, while adipose tissue has more volume. So fat will take up more space.

Kalikel

Muscle weighs more than fat, but unless you have a ton of it, it's not going to make much difference at all in how many calories you burn. Plug your info into the MFP and follow the instructions. Mid you find you're losing more than it says you will, eat a little more and see how that goes. Everyone has to tweak things to make it work for them.

rankinsect

Frankly, after two months you don't really need calculators anymore. Take your actual rate of weight loss in pounds per week and subtract your desired/estimated rate of loss. Multiply by 500. Eat about that many more calories per day (assuming you are logging accurately).

joshuakcaron

Kalikel wrote: »

Muscle weighs more than fat, but unless you have a ton of it, it's not going to make much difference at all in how many calories you burn. Plug your info into the MFP and follow the instructions. Mid you find you're losing more than it says you will, eat a little more and see how that goes. Everyone has to tweak things to make it work for them.

Yeah I misread something somewhere and thought muscle burned 6 calories more per hour (when in reality it's per day.) haha

cdcllcga01

rabbitjb wrote: »

There are lots of pictures of fat vs muscle. I've seen them on scientific teaching supply sites and the proportions are always similar

I think it's one of this out of context visual propositions to make a point, particularly when considering the solidity of each physical structure

I think you were right the first time @rabbitjb. It sure explains photos like this where she is reported as 117 lbs in the left pic and 131 lbs on the right.

cdcllcga01

http://www.nerdfitness.com/blog/2011/07/21/meet-staci-your-new-powerlifting-super-hero/

Btw - Here's the link for the above pic. Great story.

yarwell

Here's another apocryphal comparison - 250g of butter (slightly less dense than adipose tissue) and 405g of sheep's muscle and fat.