Advanced search

Can we talk about muscle weighing more than fat?

(36 Posts)
strartingtotry Mon 25-Sep-17 14:01:00

So I've been doing pole dancing which is strength training for a few months now and I've noticed I've put a few pounds on. My waist and hip measurements etc are still the same so I'm not any bigger. My arms are definitely more muscly! Do you think it's because as some people say muscle weighs more than fat?

brownfang Mon 25-Sep-17 20:12:12

The difference is less than 10%, though. Gosh, the way folk go on you'd think the difference was MASSIVE.

You could get one of those body fat% calculating electronic scales and see if there are any changes over time.

That link is also good at explaining why muscles only metabolise very slightly more energy than fat, being more muscly does not burn many more calories. I once worked out that for a woman who went from very little muscle to lots of muscle, the calorie difference per day would be like 60-80 kcal. Or a single tangerine.

strartingtotry Tue 26-Sep-17 19:03:46

Thank you for the link! I've just checked out my body fat percentage online and it's 26% which I'm happy with as I once checked and it was 33% so it's improved grin

Cameblackbenzleftwhite1 Tue 26-Sep-17 19:05:15

How on earth can you check your body fat percentage online? The scales at home aren't really very accurate

AfunaMbatata Tue 26-Sep-17 19:06:46

What camel asked, how do you measure body fat online?

YouCantArgueWithStupid Tue 26-Sep-17 19:13:33

Fat has less mass than muscle. A kg of feathers weighs the same as a kg of stones. They have a different mass

YouCantArgueWithStupid Tue 26-Sep-17 19:13:55

Sorry muscle has less mass than fat

Allthelightsgoout Tue 26-Sep-17 19:22:35

No it doesn't weigh more. A pound of fat weighs the same as a pound of muscle. It's the density which is the difference - so a pound of muscle takes up less space by volume than fat. So that's why you see heavily muscular people but trim people weighing more than people that seem objectively overweight/fat.

15 stone in a person with high muscle mass looks very, very different to 15 stone in a person with high fat mass. It's why very muscular people often have a BMI in the obese scale even though they're clearly not at all overweight objectively.

strartingtotry Tue 26-Sep-17 21:26:27

I found a calculator online which asked me to take certain measurements and weight etc and it calculated it.

I also have scales that say they tell you body fat percentage but I think that was lower like 20 % which I doubt is correct

brownfang Wed 27-Sep-17 08:17:27

Can you link to the calculator?

Excuse my cynicism... I found some pictures of pairs of people with exact same BMI. The headline was "Wow don't these people all look completely different! Isn't BMI variable!"

They didn't look different. confused Each pair looked remarkably similar in terms of visible fat distribution.

I also found some pics of individuals before & after many weeks exercise regime pics where people had same BMI both times. They did look better (more toned) in the After, but they still didn't look at all different in terms of total size, & barely different in terms of visible body fat. Maybe I'm blind?

confusedandemployed Wed 27-Sep-17 08:23:40

Ffs of course muscle weighs more than fat, in the same way lead weighs mire than feathers. Google a pound of fat v a pound of muscle, there are visual representations.

But I'd be dubious about your wondering if your extra weight is due to muscle gain. Is it TOTM? Or you could just be retaining water.

SonicBoomBoom Wed 27-Sep-17 08:30:50

It's why very muscular people often have a BMI in the obese scale even though they're clearly not at all overweight objectively.

There are very, very few people who have a BMI in the obese category (or even the overweight category) who are muscular but not fat. It's often claimed on here that athletes do. They don't.

There are actually very few Olympians that have anything other than a "healthy" BMI, even rowers, swimmers, gymnasts and sprinters. Rugby is another sport where people claim they are superfit but have an overweight BMI, but they rarely do and usually when they do they still have a bit more fat than they "should".

The only sport where the claim is usually valid is those weightlifting bodybuilders.

TheDowagerCuntess Wed 27-Sep-17 08:38:01

Must admit, I get a bit 🙄 at people who dismiss BMI because muscular people fall into the obese category.

Genuinely muscular people probably aren't too worried about their BMI, and if your Dr is telling you that you fall into the obese category, it's probably because you're overweight, not because you're ripped. You'd know if you sporting a 6-pack.

It's somewhat ironic that the quickest to dismiss BMI are generally overweight. It's a blunt tool, but so far, no-one's come up with anything close/better.

Fair enough of you're an All Black and you're contesting it, but most people aren't.

paq Wed 27-Sep-17 10:28:45

@confusedandemployed you need to revisit the definitions of weight and mass.

A pound of muscle weighs the same as a pound of fat.

A pound of muscle has more mass than a pound of fat.

reflexfaith Wed 27-Sep-17 13:45:53

a pound of muscle has the same mass as a pound of fat, but less volume, or to put it another way a given volume of fat, say one litre will be lighter than a litre of muscle

mr google he say
'Summary: Muscle density is 1.06 g/ml and fat density is (about) 0.9 g/ml. Thus, one liter of muscle would weight 1.06 kg and one liter of fat would weight 0.9 kg. In other words, muscle is about 18% more dense than fat'

Toffeelatteplease Wed 27-Sep-17 14:02:03


There's lots to suggest BMI is a poor predictor of outcomes. I think the argument was that Results tend to lump the "just overweight resuits with obese whereas they may work out healthier than "healthy weight"

I saw this myself when I lost about 4 stone of weight. I reached the just upper end of healthy BMi. I looked gaunt and ill and I was cold constantly. Whilst my BMI was (only just about) healthy, My body fat was right at the lowest end of healthy. Go figure cos I couldn't

Up to about half a stone overweight looks nd feels healthier to me. Body fat is spot on then as well.

BMI really is a bit crap

Toffeelatteplease Wed 27-Sep-17 14:09:06

A think to think off in terms of strength training is if your stomach/core muscles are working well it will hold you in tighter. DS has issues with core strength, when it's bad or he's is tired it has a little pot belly that appears. Healthy in proportion weight and height still still his ribs etc. It's just it's not held together so well.

Pilates (no other exercise) made the difference of about a clothes size for me

Toffeelatteplease Wed 27-Sep-17 14:14:18

This bit in particular

Nearly half of those whose BMIs labeled them as overweight were actually healthy, according to data on their other health measures. Fifteen percent of those who were classified as obese were also considered healthy.

SonicBoomBoom Wed 27-Sep-17 21:11:06

'Fat but fit' was debunked recently, toffee.

Toffeelatteplease Thu 28-Sep-17 06:43:30

Oh I'd like to see that.

Although really fat but fit is a massive step on from what I was saying which is simply that BMI is a piss poor measure. You need to look at other stuff as well.

BobbinThreadbare123 Thu 28-Sep-17 06:51:48

Mass is a measure of how many particles something is made of. It's measured in kilograms. 1 kg (or pounds if you're imperial) is the same amount of particles whether it is made up of fat, muscle, feathers etc. It is the same measure in any gravitational field.

Weight is measured in newtons. Weight = mass x gravity. Weight can change if gravity changes.

Density is mass divided by volume. It is a measure of how closely packed the particles are. Muscle is denser than fat, so it takes up less physical space for the same mass.

E.g. I am about 73 kg but only a size 10-12 because I'm muscly.

Anglaise1 Thu 28-Sep-17 07:00:17

This US army body fat calculator is one of the most accurate on line, not sure if this is the best link, there are others which have been posted. My scales give me a body fat of 14%, this 17% which is probably more accurate.

AdalindSchade Thu 28-Sep-17 07:01:20

Nearly half of those whose BMIs labeled them as overweight were actually healthy, according to data on their other health measures. Fifteen percent of those who were classified as obese were also considered healthy

What does that mean though? I’m in the very overweight category and I am healthy as in I have no health conditions but my weight is an objective health risk for the future so I’m not as healthy as a person of normal weight.

BoobleMcB Thu 28-Sep-17 07:08:26

1lb of me weighs the same as a 1lb of a new born but I can GUARANTEE I weigh more than a new born

Toffeelatteplease Thu 28-Sep-17 08:24:08


I'm guessing they were looking at other measures like body fat.

I did look at another study (when I was trying to work out where to stop losing weight) that was actually looking at other long terms outcomes like health conditions etc. From memory that came up with stuff like a little bit underweight was a lot worse outcome wise than being obese (although obviously different associated health issues) with a little bit overweight doing aso well as healthy weight. Not sure I could find that one again though.

Join the discussion

Registering is free, easy, and means you can join in the discussion, watch threads, get discounts, win prizes and lots more.

Register now »

Already registered? Log in with: