Does bmr drop as you loose

balancedbrunette

Just wondering does bmr drop significantly as you loose weight and should i be keeping account of this figure a lot?

yarwell

yes, it can do. It's largely driven by fat-free mass so losing that reduces it. There's a tendency to be less active while dieting too, reducing TDEE for the same BMR.

Generally speaking we're talking a couple of hundred calories

55in13

I have read about some studies that found an average of 4% to 10% drop in metabolism by overweight people on a diet. I have seen much higher figures for some poor souls that were starved to stick figures and some people promote those numbers as the norm. They are not. I have also seen people use the more reasonable numbers but claim that your metabolism will slow 2.5 times as much (appears to be possible) if you don't do X (the study I read about couldn't correlate specific causes to be at either end of the range).

The important thing to note, IMO, is that I have never seen any medically sound study that found a point at which decreasing your input does not increase the deficit. A slowing metabolism might make that less than 1:1 at some point and there are sound reasons not to go too low, but being washed out to sea in some metabolic undertow is not reality.

EDIT - One sort of obvious thing - it takes less energy for a 175 pound guy to run a mile than a 225 pound guy. That's simple physics; moving 2 different masses the same distance, the larger mass requires more energy. But both guys are me. Every breath I take moves a slightly lighter chest.

whierd

Yes, your BMR drops as you lose weight.

balancedbrunette

thanks for the replies need to go over my figures

paxbfl

Check out this calculator. You can put in different weights and see how it affects BMR.

http://scoobysworkshop.com/accurate-calorie-calculator/

My BMR was 2093 when I started 48 pounds ago... now it's 1875. So yeah... you have to make adjustments as you go along but it's a small price to pay. I feel so much better these days it's easy to burn more calories via exercise so not a big deal.

Hope that helps!

Showcase_Brodown

Yes, it will lower some as you lose weight. The weight you carry around does require some energy to maintain. Lean mass will require more. I believe it is something like 6 calories a day for a pound of muscle and 2 for a pound of fat. You won't have to worry about this too much as the MFP app will adjust your recommended calories to a ballpark amount based on your current weight. As long as you are not in a severe deficit, any drop in metabolism should be fairly predictable.

PriceK01

I read that it's a good idea to make adjustments to all of your calculations with each 10 pound change in body weight. I do it every 5, because I'm spastic like that

If you use any gadgets (HRM, fitbit, smartphone apps, etc) make sure to update those, as well

erikkmcvay

I adjust my goals every 5 lbs I lose. Helps keep you inline with what's required to keep losing.

55in13

If you use any gadgets (HRM, fitbit, smartphone apps, etc) make sure to update those, as well

My burn for running 5 miles dropped from over 900 to under 700 when I remembered to update the app settings. Little mistakes like that are one reason I am a little leery of the "eat back exercise calories" idea (I don't do that).

melindasuefritz

yes

myofibril

yes, it can do. It's largely driven by fat-free mass so losing that reduces it. There's a tendency to be less active while dieting too, reducing TDEE for the same BMR.

Generally speaking we're talking a couple of hundred calories

Pretty much this...

melindasuefritz

mine will drop from the obese category to the over weight catergory after i lose
35 pounds... and im almost there
MY BAD IM TALKING ABOUT BMI
SOrry

linsey0689

yes!

h9dlb

No. If you did little or no exercise before, and now start doing exercise such as cardio or lifting your BMR will increase, even though you are cutting !

I think people answering yes here are confusing BMR (Basic Metabolic Rate) with BMI (Body Mass Index) and TDEE (which will decrease)

55in13

No. If you did little or no exercise before, and now start doing exercise such as cardio or lifting your BMR will increase, even though you are cutting !

I think people answering yes here are confusing BMR (Basic Metabolic Rate) with BMI (Body Mass Index) and TDEE (which will decrease)

No, we are considering that weight loss means eating at a deficit, which some studies show to cause a slight decrease in BMR and that a lower body weight means a smaller mass to keep warm, a lighter chest that rise and falls with each breath, etc. It isn't generally by a huge number but it does decrease.

EDIT - The OP said nothing about exercise BTW. Even figuring exercise in, I have not seen any studies that show an increase in BMR while eating at a deficit.

h9dlb

Are you seriously denying that if you start an exercise regime or increase an exercise regime your metabolism will not increase, irrespective of a calorie deficit and fat loss? Otherwise what's the point in doing any exercise!

55in13

Are you seriously denying that if you start an exercise regime or increase an exercise regime your metabolism will not increase, irrespective of a calorie deficit and fat loss? Otherwise what's the point in doing any exercise!

The point is you burn calories while you do it and there is the potential of gaining muscle which will increase BMR, but the subject of whether or not you can gain muscle while eating at a deficit is pretty debatable in itself. Given the OP's question, which does not mention exercise but does ask about weight loss (which we assume means a calorie deficit and fat loss), I was not answering irrespective of calorie deficit and fat loss; that was the context of the question. Anyway, the info I have seen leads me to believe that some people can get a slight muscle gain in deficit. Whether that offsets the lowered BMR due to the weight loss I cannot say for sure, but I don't think so. I have an open mind though; please cite your source.

h9dlb

The original question was "Does BMR drop as you lose weight?". Several people answered yes. My point is this is not necessarily the case, because if you exercise while cutting, BMR will increase.

Calorie burn just does not come from the exercise itself, but also comes from the "afterburn" in the hours post exercise when the metabolism is increased whilst the damaged muscles are being repaired, depleted oxygen is being replaced, phosphates are turned into creatine, fat stores are broken down into free fatty acids and hormones are put in check. For your body to do this requires energy, hence fat burning and increased metabolism. The after burn from heavy weight training is much greater (lasting upto 36 hours) than the afterburn from cardio, which is only a few hours.

As for citations, its a bit too late for me to go into it now but google "EPOC" - Exercise Post Oxygen Consumption which explains why metabolism is increased after strenuous exercise, irrespective of being on a cut or not.

By the way many congrats on the 50lbs

55in13

Thanks! I feel a lot better without that extra weight. Still some to go but I see the light at the end of the tunnel.

I have looked into EPOC some as I have tried to do HIIT from time to time. There is a pretty good WikiPedia article (really good compared to some, this one is almost purely a bunch of cited study quotes):
http://en.wikipedia.org/wiki/Excess_post-exercise_oxygen_consumption
It backs up your 36 hour claim and even raises you 2 hours.

I say "tried to do HIIT" as I am not sure I ever really do it hard enough to really make that much of a difference. I know I am trying to put the cart before the horse to some degree; it seems like this awesome way to get your metabolism going so you can get in better shape, but you need to be in pretty good shape to do effective HIIT.

But we digress; the OP's question didn't mention exercise at all, just weight loss. My BMR has dropped as I lost weight and I think the OP's will also.

h9dlb

HIIT gets easier the more you do it, and is great for fat loss, and takes such little time compared to steady cardio, I also find it less boring (I hate cardio). You only have to do 20 mins. Perseverance and consistency is the key

If you are struggling just sprint for 30 seconds then walk for a minute and a half. As you progress increase the sprints to 45 seconds and reduce the walking to a minute. Then when you get fitter, drop the walking and do a light jog for 30 seconds. Alternatively (assuming you are using a treadmill) in between sprints walk on a 12% incline.

Treadmill is best for HIITS, but if you are finding it really difficult, do it on a bike, rower or kettlebell circuits, whatever you are most happy doing, as training shouldn't be a chore / de-motivating

55in13

Straying from the OP's topic on this interesting tangent...

Running has been my primary exercise. I did the C25K early this year and just kept running longer and longer. Now I generally run 6 or 8 miles at a time, 3 or 4 times a week. I just started a conditioning coach program at the Y so I am starting to get more into gym based exercise, though I did give the preference for things I can get done elsewhere on days I can't make it without much equipment - body weight, a few dumb bells and a kettle bell. Anyway, when running I have run as far as 10 miles without stopping or walking, but they were 11 minute miles. So it took me close to 2 hours. I can run that long at 5.5 mph. The times I have tried adding in sprints, I get in maybe 3 true sprints and I am toast, whether I ran 5 minutes or 50 before I sprinted. That is why I say I have tried but I am not really sure I did enough to benefit from it. The problem I have with HIIT running is that the thigh burn just stops me dead in my tracks. I just can't run after that until a fair amount of time has passed. The idea of trying it with the kettle bell is really appealing to me because I could switch exercises to try to keep from overworking something that pulls the plug on the whole session. Maybe...

h9dlb

Steady state cardio burns muscle and should be avoided as less muscle = lower BMR. That's why doing 20-25 mins HIIT is more effective as it burns more fat and less muscle, therefore better results for less effort and time.

Doing lots of cardio is counter productive to fat loss because the body needs energy as quickly as possible to meet the demands being placed on it, and when glycogen stores are depleted the body starts burning muscle (as opposed to fat) to quickly release energy.

Compare a marathon runner's body (skinny) to a 100m sprint olympic athelete (muscular ripped). Body builders tend to avoid all cardio as they do not want to lose any hard earned muscle.

Rather than running for 2 hours, you would get better results doing 30 minutes heavy weight training to maintain muscle mass and increase your BMR for 36 hours due to after burn, followed by 20 mins HIIT (total 50 minutes)

yarwell

Are you seriously denying that if you start an exercise regime or increase an exercise regime your metabolism will not increase, irrespective of a calorie deficit and fat loss? Otherwise what's the point in doing any exercise!

Depends how you are using the word "metabolism". Exercise does not automatically increase your Basal Metabolic Rate.

I am unclear about your last point. Exercise may increase your TDEE which would be "the point", and it may help preserve lean muscle mass while at a calorie deficit, which in turn helps retain BMR.

Lyadeia

Steady state cardio burns muscle and should be avoided as less muscle = lower BMR. That's why doing 20-25 mins HIIT is more effective as it burns more fat and less muscle, therefore better results for less effort and time.

Cool story, bro.

Tell me more, as I love to read broscience on the forums. :yawn:

balancedbrunette

Thanks for the replies everyone, know myself i need to keep track of my figures a bit more, have lost the last 10lbs but havent gone over my bmr/tdee and need to do this now.

Check out this calculator. You can put in different weights and see how it affects BMR.

http://scoobysworkshop.com/accurate-calorie-calculator/

My BMR was 2093 when I started 48 pounds ago... now it's 1875. So yeah... you have to make adjustments as you go along but it's a small price to pay. I feel so much better these days it's easy to burn more calories via exercise so not a big deal.

Hope that helps!

thanks for the site, will check it out.

balancedbrunette

But we digress; the OP's question didn't mention exercise at all, just weight loss. My BMR has dropped as I lost weight and I think the OP's will also.

Sorry for the confusion here probably should have mentioned exercise but was just inquiring in general, at least it opened up an interesting discussion as i was curious about the HILT training myself.

I made the mistake last year of going straight into cardio treadmill sessions to loose weight which benefitted me for some time however now i'm doing strength training alongside kickboxing and its much better. At the stage where i don't want to loose anymore just tone up. Anyways thanks everyone for your information.

GauchoMark

Are you seriously denying that if you start an exercise regime or increase an exercise regime your metabolism will not increase, irrespective of a calorie deficit and fat loss? Otherwise what's the point in doing any exercise!

It seems you are confusing BMR with TDEE. BMR by definition does not include exercise.

To the OP, your BMR may change slightly as your weight changes because, as Yarwell posted in the first reply, BMR is driven primarily by fat free mass. So, if you lose or build muscle, your BMR will change slightly. The TDEE can change pretty significantly, though, as you become more/less active and as you are not carrying around so much weight.

paxbfl

Steady state cardio burns muscle and should be avoided as less muscle = lower BMR. That's why doing 20-25 mins HIIT is more effective as it burns more fat and less muscle, therefore better results for less effort and time.

Doing lots of cardio is counter productive to fat loss because the body needs energy as quickly as possible to meet the demands being placed on it, and when glycogen stores are depleted the body starts burning muscle (as opposed to fat) to quickly release energy.

Compare a marathon runner's body (skinny) to a 100m sprint olympic athelete (muscular ripped). Body builders tend to avoid all cardio as they do not want to lose any hard earned muscle.

Rather than running for 2 hours, you would get better results doing 30 minutes heavy weight training to maintain muscle mass and increase your BMR for 36 hours due to after burn, followed by 20 mins HIIT (total 50 minutes)

Thanks for this. After losing 48 pounds, I'm close to my ideal weight and am currently training for a half-marathon. So I'm running a lot. But I plan to really shift the focus to muscle-building after my race in the Fall, so I will bring back HIIT in moderation (which I was doing initially to drop the weight).

I've been wondering about how body type influences this too... I'm an "endomorph"... I build muscle very easily but tend to pack on fat also. Through all the weight-loss, I haven't seen the loss of muscle I would have expected. A body fat measurement says I lost 4 pounds of fat and gained 2 pounds of muscle in the past 4 months (which I thought was virtually impossible). Obviously this may not be 100% accurate but it feels about right - my weight has dropped and my strength has increased.

I doubt that I'll ever look like a marathoner no matter how much I run. Still I think your point is valid - and I want to maximize my muscle gains when I shift my focus to that.

siyeonsimpp

yes, definitely, since your BMR is a calculation between your age, height and weight, when one variable changes, it will increase/decrease depending on which direction it changed. I've lost 7 pounds so far using MFP and my BMR dropped from 1800 to 1200 already.

AnnPT77

jungkooksdonut17 wrote: »

yes, definitely, since your BMR is a calculation between your age, height and weight, when one variable changes, it will increase/decrease depending on which direction it changed. I've lost 7 pounds so far using MFP and my BMR dropped from 1800 to 1200 already.

This was a thread from 2013, and boy did it include some incorrect stuff.

I think some of the people didn't realize that BMR is pretty much the calorie level a person would burn in a coma, and that daily life activity burns calories on top of that, and intentional exercise adds to the total. TDEE (totall daily energy expenditure is the all-day calorie burn from BMR + daily life + exercise + plus some other small stuff. Also cardio doesn't inherently "burn muscle". Bodies don't like to burn useful stuff, and pretty much only burn muscle if one's overall calorie deficit is unreasonably large. Jeesh. So much misinformation in this old thread! 😬

As an aside, the BMR, NEAT (non-exercise activity thermogenesis, calorie burn from everything except exercise), and TDEE calculators do take age, height, weight, etc., as input, but all they're giving you is a statistical estimate. Your actual TDEE can vary from those estimated numbers for many reasons (usually not by much, but for the rare person the estimates are quite far off), and our real TDEE will be different every day (by a bit).

I really don't belive your BMR will have dropped by 600 calories (33%) from a 7 pound weight loss. Your calorie goal may have changed for some reason, but BMR (the "burn in a coma" number) wouldn't change that much for so small a weight loss.

Congrats on your nice loss so far, and best wishes for continuing success!