Wednesday, July 16, 2014

Metabolic Testing: What's My Resting Metabolic Rate?

Back again with more details on my update! This is something I was always interested in but could never find access too until recently, so I hope you will find it interesting as well. This spring, I found out that a nearby hospital was offering a new service: metabolic testing. They'd purchased an indirect calorimeter... this one: the ReeVue Indirect Calorimeter. According to the website, here's how it works:

"ReeVue by KORR directly measures the concentration of oxygen breathed out by each patient.  The patient merely breathes through a simple mouthpiece as all the exhaled air is collected and analyzed.  Because there is a direct correlation between oxygen consumed and calories burned (4.813 calories for every milliliter of oxygen consumed), an accurate measurement of oxygen consumption is an effective measurement of calorie consumption."

This testing is very accurate and done in a medical setting. It was easy: you go in fasting (in the morning) and having not exercised in the past day (no problem!). They have you recline on a bed, dim the lights, play soothing music and tell you to relax for a few minutes. Then they put a tube in your mouth with a mouthpiece that seals the edges, and they put a clip on your nose and leave you to relax for ten minutes. She told me to just lie there, try not to move, think calming thoughts, breathe naturally.

When the test is completed, you get a printout:

At the bottom is the important stuff: the results of the metabolic testing. On the back of this sheet there are explanations of the results. It says: "Today we measured your RMR (resting metabolic rate). This is the number of calories your body would burn if you did nothing more than sit in a chair all day. This is similar to what is known as your Basal Metabolic Rate (BMR)." This measured number is also called the REE, or resting energy expenditure. My measured REE (RMR) was 1440 calories/day, much lower than predicted by the usual equations for a woman my age, height, and weight.

The explanation states "Many studies have been done to determine what is 'average' or 'normal' metabolism. Your metabolic rate has been compared to what is 'normal' for your age, height, weight, and sex." Predictive normal for a person with my stats is the center line. My metabolism is "Slow (-19%)."

The graphic (below) of energy balance shows an estimate of what I would burn with average activity and exercise. This would be 1440 calories (RMR) plus lifestyle and activity ("calories you burn performing your daily activities... working, playing, eating, etc") which is estimated at 432 calories, plus 150 calories burned during 30 minutes of moderate exercise per day, for a total of 2022 calories/day. Under "how much to eat" it shows my weight loss zone, WITH lifestyle activity and exercise, is 1152 to 1440 calories/day. And Maintenance Zone is 1440 to 1872 calories/day.

You know what, I am shocked. The test validated what I thought was going on for the past 2 years. I had really started to doubt myself and think I was wrong in what I'd believed all this time. I wondered if I was counting wrong or measuring wrong or making some mistake with my efforts. I had counted calories for weeks, months, and have blogged many times my frustrations at not losing weight when I was eating at a level that SHOULD give weight loss... gaining weight eating 1700 calories, maintaining at about 1500 calories, and only losing very slowly when I ate 1300 or less. Given that my activity level with the plantar fasciitis and torn tendon was pretty much "sitting in a chair all day," it finally makes sense. I was only burning about 1440 calories a day, so I could not lose weight eating at that level. I don't *like* the results... but it does make sense. In order to lose weight, I have to eat between 1152 and 1440 calories AND have an active lifestyle AND exercise 30 minutes/day. In fact, both the dietitian and the endocrinologist said that I should aim for 1100 calories per day, which is on the lower end of the "weight loss zone" recommendations, because I am just not as active as the 'average' person. And yes, that is *with* the 30 minutes of exercise per day... 1100.

I feel more confident about how well I know my body after having this testing done. This information will be very useful for me in the future when I am done with my elimination diet and start counting calories again. I think in the future, as I become more active and build muscle and lose fat, I will go back and have this testing done again when I am closer to my goal weight to see if I am able to speed up my metabolism. And yes, I think, and my endocrinologist believes, that eating 900 calories a day for such an extended period of time as well as being so inactive this year contributed to such a slow metabolism. Thinking back, I really wish I had just done Medifast for that first 8 months when I lost 59 pounds, and then gradually and slowly increased both my calories and my exercise. It would have been a lot easier to do at 175 pounds than it is now, and my metabolism would have probably been fine. My mistake was to keep going back to Medifast over and over, cutting my calories super low while not exercising much. Lesson learned, and I hope you learn from my mistakes so you don't have to live through them.


Janet said...

I recently (04/15) checked myself into the medical weight management program at Wake Forest and the FIRST thing they did was the RMR (resting metabolic rate) and BIA tests. My RMR is 1,730 so losing weight on a 1200-1400 calorie diet was going to be (and always has been) painfully slow!

After exactly 3 months (yesterday, 07/15) I am down 61 pounds and FINALLY feel like I am gaining control over my emotional eating (I believe what I weigh is more due to how I feel/don't deal with emotions) than it is about what I eat.

Good for you for having the test done! Knowledge is indeed power and I am looking forward to what we'll both achieve with it!

Always wishing you my best!


Margaret said...

Hey Lyn,

I wish everyone going around telling people who are not losing weight to eat more could read this post. That's the reality of it.


Tracy said...

Here, here on what Margaret said.

My cousin has Hashimoto's as well and I know what a struggle it has always been for her to maintain, let alone lose weight. I have long read your blog Lyn (but I'm kinda quiet) and I wish you all the best now. Knowledge is power and now you know.

I'm curious as to whether you had time to discuss with the dr. the impact of Medifast and whether, in light of what you now know, if you will be changing any of the MF support info you have on your site?

Lyn said...


congratulations on the loss! That is wonderful! So glad you found a program that works for you.


well, I did try the "eat more to lose" thing a few months back, like 1800-2000 a day if I recall correctly, and gained. I did ask the dr about that and he said that IF there is such a thing as "healing your metabolism" (which basically means raising it) it would be done by slowly and gradually raising calories AND exercise while maintaining the same weight.


I did discuss it, which I mentioned near the end of the post, and no, I don't think I will change any info here at the present time. If people do the program as directed and then a gradual reintroduction of food as the transition program recommends, I think they'll do fine. It's just the on and off, long term (years) staying on that plan than I think is a bad idea.

timothy said...

so now you know, and knowledge IS power! sounds like you'll be able to implement a plan specifically for you and not the cookie cutter one size things that NEVER work! WONDERFUL!

kim ellis said...

so its lose the weight muscle so you can eat more and your metabolism stays high.....

Betsey C. said...

Lyn, thank you so much for your honesty and all the interesting things you post here.

It has always been my opinion that "crash diets" are harmful in the long run. I am a true compulsive overeater, I always want "more". I have gone on many diets in my life, but never anything restrictive that limited food categories like low carb.

I am 60, not very active, I just walk a bit here and there. I have been able to lose almost 40 lbs with Weight Watchers since February. My problem, of course, is keeping it off! Maybe this time.........

I know that you will be able to improve your metabolism, Lyn. You are so smart, and you do your research. It may take a while, but you will do it!

Lori said...

That is very interesting. I had a dietitian insist that people did not lower their metabolisms on very restricted diets. I didn't believe her then and now I have proof.

I wish you all the best getting your calories where they need to be and increasing your activity. You have the determination to make it happen.

Anonymous said...

@ Lori, re: " I had a dietitian insist that people did not lower their metabolisms on very restricted diets. I didn't believe her then and now I have proof."

This result is not proof that a restricted diet lowers metabolism. To do that, you'd have to compare two test results side by side, one before the restricted diet and one after. Even then, due to the weight loss changes also affecting metabolism (you need less calories to maintain a smaller body), it would still be a mystery. Also, even though reducing calories does reduce your metabolism, the question is, by how much, and does this affect weight loss, and finally, is it permanent or is it only during the weight loss phase.