DOOM_NX

Hello guys,

I just got home from my last visit to my dietitian. I got my first RMR measurement.
In short the device showed:

RMR: 896 kcal/day
VO2: 129 ml/min
Ve: 3.6 l/min
Rf: 13.2
FeO2: 16.73%

%Var VE: 13.8%
%Var VO2: 22.3%

%Pred (Harris Benedict): 40%

21 years old, 238 pounds, 5' 6".

Is there anything wrong with me? Every calculator I used in the past said I should be burning around 2100 calories per day without doing a thing. My body fat percentage is around 30%. What should this 896 number mean to me? Do I need to eat less? Currently I'm eating around 2000 per day and losing 2 lbs per week.

Thanks in advance.

LazinCajun

I'm not an expert, so take this with a grain of salt.

If you're losing weight that isn't 100% water weight, then you're burning more calories than you're taking in. I think this is the case since it sounds like you're consistently losing weight.

If I understand it correctly, RMR is a measure of how many calories you'd burn if you do nothing but rest for 24 hours. You technically will use more calories than your RMR if you lay on the couch all day, but go to the fridge to make lunch.

I'd say keep at it as long as you're losing weight at a healthy rate (1-2 lbs/week). Keep in mind that if your exercise level remains constant, your body will need fewer kcals as you lose weight, so you may have to cut back and/or exercise a bit more later as the pounds continue to come off.

Edited to ask: Did your dietitian recommend 2000 calories a day? If so, I definitely wouldn't worry about it, especially since you're still seeing results.

chasm54

THe RMR figure must be wrong. 1896, maybe?

CraigB

Did you ask these questions of your dietician when you were there?

DOOM_NX

Well, I asked if this is right and she said this machine is really accurate and it can't be wrong. Then I said "but we asumed I was burning 1000 more doing nothing!"
And then I asked "So why am I not gaining weight then?"
"Because u exercise"
"Bullcrap, I only exercised once during the past 2-week period"
"Don't worry, go on with ur exercise and we'll measure it again. Maybe that's why u had hard time losing the 1st month."

So, this is what she said. I'm not worrying, I'm just trying to figure out whether we took a bad measurement or I have the metabolism of a bear in the winter.

Bear with me guys, if my resting metabolic rate was 900 calories. I would burn even less accounting for 8 hours of sleeping and being on the PC all day. But let's add my exercise to that 900 figure. 1h of cycling burns approximately 500 calories, so I burn 1400 per day. And I eat 2100. 700 calories surplus. Shouldn't I be gaining weight? Wtf.

The device measured my gas through a mask for 6 minutes while I was sitting on a chair. I'll provide a link soon.

chasm54

No, she doesn't know what she is talking about and is falling into the usual trap of believing that the machine must be right. Any adult burns more calories than that just staying alive. Forget it, you've been losing weight just fine. On doing what you're doing.

BionicChris

Please somebody correct me if I am wrong, but when you exercise your body metabolism speeds up for a period after the exercise as well.

In addition to the 500 calories you burn off cycling, your resting metabolic rate is now an active metabolic rate - it will be higher than the 896 quoted. I don't know how much that can vary by though.

Mithrandir

What does something like that cost anyhow? And how would I be able to find someone who could perform the measurement?

I'm beginning to think there's something off with my calculations. My old Polar heart monitor said I burned about 90 calories per mile, and my Garmin Edge says I burn about 40 calories per mile.

Both of these numbers must be extremely inflated, because I should be losing weight left and right, but I've been steady at 357ish for over a month now. According to Garmin I've burned 40,000 calories in the past 30 days, which averages 1,333 per day. Combined with an 1800 calorie diet, that means I'm only taking in 467 net calories per day, which seems like it's far lower than what the average humans BMR is.

Going to talk to my doctor about this later this month when I have my next appointment, but I'm getting disillusioned about my lack of progress lately. I lost 3 pounds a month steadily for the first 9 months of this program, and the weight loss has steadily slowed down to nothing.

LazinCajun

Indeed, looking again, that number seems way off.

https://www.caloriesperhour.com/index_burn.php Plug in your stats here, and you'll find that 1800 calories is a lot closer than 800. While the formula in the calculator won't be 100% accurate, it should give you a ballpark number... I think you'll find the measurement is wrong. I've heard of technicians messing up VO2max measurements quite often.

sstorkel

Both of these numbers are wildly inaccurate. If you really want to know how many calories you burn while cycling, borrow a PowerTap power meter for a day. If I ride so hard I can barely stand when I get off the bike, I burn 550 calories/hr. Usually, it's more like 500 calories/hr. That's for a ride that's reasonably flat (0-500ft of elevation gain) at a brisk pace (16.5-17.5mph). In contrast to the PowerTap, my Garmin Edge 705 reports that I'm burning 1200 calories/hr! I believe the newer Edge models aren't quite so optimistic, but I still wouldn't be inclined to trust them...

Sayre Kulp 

That doesn't add up to me. My resting metabolic rate is just over 2300 per day and my body fat % is around 16%. My BMR was higher when I was bigger, so logically... get where I'm going with this?

DOOM_NX

Thanks for your interest guys.

The machine used was Cosmed Fitmate. It's an Italian piece of hardware that measures your VO2 while resting and calculates the calories you burn. It should be accurate but it was giving an error about air escaping during the first minutes of the test. But she reassured me it ended right. I don't know if we messed up during the measurement but I'm kinda worried my RMR is THAT low. I used to think BMR is closely related to lean mass and I have 165 pounds of it. But now I see this is not the case. I'm gonna read more to get this thing right.

Oh, someone asked about the price, it costs 20 EUR to have this test done here in Greece but she didn't charge me. However she told me to tell others that might be interested that it costs 20 EUR.

goldfinch

No way, no how.

As a point of comparison: I am 4'11" and 112 pounds and 56 years old. My body fat percentage remains too high, at 30%. My resting metabolic rate is in fact very low, only about a 1000. I do not have near the lean body mass that you do. And yes, metabolic rate is highly influenced by the amount of lean body mass you have.

DOOM_NX

I don't know goldfinch...

I just did some research. Indirect calorimetry through VO2 tends to be accurate. This machine has an accuracy of ±2%. So either we messed up the process or my preparation was not good enough. Otherwise, I really have a slow metabolism. My only concern is the calorie balance. The numbers don't add up!

sstorkel

Sounds like the number they gave you is off by 4-5X or more. What's the most likely explanation? That you have a RMR lower than any other equivalently-sized person on the planet? Or that your dietician screwed up the test and gave you an incorrect result?

jimnolimit

that test should mean nothing. you're losing 2lbs a week, what's the problem?

a pound a fat is about 3500 calories and you are losing 2 pounds a week, you're burning off about 7000 calories a week or 1000 calories a day. if you're eating 2000 calories a day while this is happening, you're burning about 3000 calories a day total.

jimnolimit

your numbers don't add up. if you're 350lbs and exercise regularly while only eating 1800 calories a day, you should be losing weight fast. how accurately are you measuring your food/calorie intake?

Mithrandir

Pretty accurately. The only thing that's changed since losing 3 pounds a week is the fact that I exercise around 12-15 hours a week instead of just 5.

jethro56 

It's amazing how quickly the human body adapts. Especially if you've been on "the journey" for awhile. Last fall/winter I was cold all the time. I had my thermostat set at 77 and felt cold. Now 70 degrees feels fine, just as it used to before the weightloss. I think this has some correlation to BMR. I think the same can be said about exercise. If you keep doing the same thing your body becomes very efficent at whatever it is. I love to ride but it's become extremely difficult to get my heartrate up while riding. (having too much fun just looking at stuff)

DOOM_NX

Funny thing is, I stopped riding regularly for the past 2 weeks cause of the weather and THEN I saw a huge change on the scales. Oh well... As long as I'm losing I won't worry too much...

Mithrandir

Agreed. 2 Winters ago I used to keep my heat at 70. Last winter I had to set it to 65 or else I felt like I was burning up. I wasn't able to sleep last night because I was too hot, even though it was 62 in my apartment. Eventually I had to turn the AC on at 58 so I could fall asleep. Didn't help much because I got a crappy sleep and ended up being too tired to bike to work today. Sigh.

As far as heart rate; here's my monthly average heartrates/speeds while cycling:


Heartrate goes down, speed goes up. I think I've reached that "plateau" point where the body has become so efficient at cycling that I'm no longer burning very many calories doing it. Glad skiing season is starting. Maybe a few months off of cycling will jumpstart my weightloss again.

DOOM_NX

Regarding your temperature, it's said that people with fast metabolism tend to heat up very easily. People with slow metabolism tend to be cold.

jimnolimit

I'm not a professional, but if you weigh 350 and you're exercising 12-15 hours a week, and you're only eating 1800 calories a day, your basically starving yourself. This might sound counter intuitive, but you might have to bump up your daily calorie intake, especially to support your exercising.

Mithrandir

Some further analysis.

I weighed 380 pounds when I first stepped on the bike again in May. Today I weigh 357, a total loss of 23 pounds. I guess on paper that sounds good, but we're looking at about 6 months here, so I'm kind of disappointed. If I continue at this rate it'll take forever to reach what I consider a reasonable weight. Regardless...

My Garmin, since May, says I've burned 164,531 calories. Since when you're working out, your body typically takes calories from both immediately-available carbs and by burning fat, you typically only burn 50-60% of those calories as fat. So let's say 55% of my calories were burned as fat; which means I burnt approximately 90,492 fat calories. A pound of fat is 3,500 calories, so divide by that and we get 25 pounds.

Interesting. Pretty close to 23 pounds. Perhaps the Garmin figures aren't all that off after all?

Mithrandir

I put part of the blame on wider blood vessels too. My blood pressure has dropped dramatically, so blood flows faster and freer through my veins, thus transferring heat much more efficiently. Given that I still have quite a large amount of adipose tissue around myself, I think I'm in an odd situation where my body is unintentionally being too efficient at warming myself up, and my fat is trapping the heat in.