Friday, May 28, 2010


As you might remember, I was so discouraged after getting the results back from my body composition test at my doctor's the other day.  According to that test, I had 40.1% body fat, and it had gone up substantially since August 2009, when it was 35.2%.  That means, according to this test, that since then, I had gained 5.9 pounds of fat and had lost 8.5 pounds of muscle.

I was so confused by this, because my weight is basically the same, and my measurements are basically the same.  How could I lose that much muscle and gain that much fat?

Well, I was so depressed, that this morning I arranged to have a Bod Pod body composition test done at The East Bank Club in Chicago.  I just couldn't help but feel that maybe the machine at my doctor's office was wrong.

Steve, the trainer who did the test, said that their machine is calibrated regularly, and the results are the same as a water dunking test.  I paid my $65 (if you are a member there, it is only $40), slipped off my shorts and shirt to reveal my bikini underneath, tucked my hair into a swim cap, and stepped inside.

The whole test took about 5 minutes or less, and I got a nice print out of my results.  I was really nervous.  What if it said that my doctor was right and I am 40.1% body fat?  As it turns out, my body fat is only 36.5%, which is a lot closer to what I believe it is.  So this means (and I choose to believe it is true) that my fat weighs 51.2 pounds.  I want to get down to 130 pounds with 25% body fat, so I need to lose 18.7 more pounds of fat to reach my goal.  Since my lean mass weighs 89.3 pounds, I will need to put on another 8.2 pounds of muscle to reach my goal.

It also says that my RMR (Resting Metabolic Rate) is 1139.

Supposedly, if you believe that we can depend on calories burning the way they do in a petri dish, that means that, in order to maintain my weight if I was laying in bed all day and not moving, I would need to consume 1139 calories per day.  This number is based on my lean mass and age.  If I am sedentary, which I pretty much am right now, I would need to consume 1412 calories per day to maintain my weight, which is 1139 multiplied by 1.24.  And the more active I am, the more calories I need to maintain my weight.

Okay, there are a few things that spring to mind about this scenario:

First, a calorie is not a calorie is not a calorie.  If you are eating low carb and high fat, you can consume hundreds of calories more of food than if you are eating high carb and low fat.  So who's to say what my real RMR is?  It might be 1339 or higher...

Second, this number supposes that all calories are burned for fuel.  From the reading I've done in books and on the internet, if you are eating the right amount of protein, that protein is going toward rebuilding muscle and other things and is not "burned" as fuel.  So should a certain portion of protein even be counted toward the calories you "need" each day?

Third, everyone's metabolisms are different.  If my metabolism is slow because of any number of reasons, including illness, hormonal imbalances, the type of food I eat, then how can anyone tell me that my Resting Metabolic Rate is 1139?  My personal metabolism may be much slower than that.  And the opposite would be true, too.  A person might just naturally have a very high metabolism, in which case their RMR might be a lot higher than 1139.  To arbitrarily say that, because I am 54 years old and have 89.3 pounds of lean mass, my RMR is 1139 is just silly.

Fourth, we really have no way to know how "calories" are untilized by our bodies.  Just because a piece of food burns and heats up water to a certain degree in a lab, does not mean that's what it does in our bodies.

And lastly, you could lock two people in a room and give them the exact same food, and make them do the exact same exercise, and one of them would lose weight and the other would not.  The RMR charts do not account for this.  They just say, "Eat 250 calories less and exercise 250 calories more each day for seven days and you will lose a pound!"  Yeah, right.

So what do I do with this information?  I think that using these calculations might be a starting point if you are trying to think about how much to eat.  But you should be prepared to increase or decrease what you are eating based on how you do, knowing that your RMR might be higher or lower than what the charts tell you.

You also need to be aware that the breakdown of the macronutrients you are consuming may significantly alter your RMR.  If you reduce carbs, and increase fat, for instance, that could raise your RMR, and mean you can eat more.  If you increase carbs and reduce fat, you could lower your RMR.

My opinion, which is subject to change, especially on this subject, is that it matters how much we eat, and the ratios of fat, protein and carbs matter, too.  But do I believe that in order to lose a pound, you need to have a 3,500 calorie deficit?  Most decidedly, no.

But now that I know that I have more muscle than I thought I did, I am going to increase my protein by another 20 grams.  I have been gaining a little lately, and it may be that I am not eating enough.  That will give me another 80 "calories" each day.  Sorry, but I have to call it something!

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