Ok, I've posted some heavier-I-needed-it-off-my-chest stuff lately. So I thought I would switch it up here. On my mind, as a trainer, I'm always wrestling with what to say when people tell me they need to lose 'x' amount of weight. It's one thing if they are my client. I get down to it. But when it's random people - friends, family, neighbors, whoever- I struggle with what to tell them. "I need to lose 20 lbs." Ok, so do I agree? Do I deny it? Here's what I want to say.
Let's do the math to really find out how much weight you need to lose. I'm going to give a couple of examples so that we can see what really needs to happen. It's all science. RBW= LBM / (1-DFP) What does that mean? Recommended Body Weight (RBW) - This is the weight you should be according to science. Lean Body Mass (LBM) - Everything that is not fat: muscle, bone, intestines, etc Desired Fat Percentage (DFP)- The body fat percentage that you want to be Please remember that when you choose the body fat percentage you would like to be, you need to look at what is healthy. So let's take a look at a few people. Jenny is 150lbs with a body fat % at 24%. She is in her late 20's and therefore would like to get down to 18% body fat. Let's fill in her formula: RBW=114 / (1-0.18) To find LBM take the weight and multiply by the fat % (150*0.24=36). Then subtract the fat weight from the total body weight (150-36=114). RBW=114/.82 = 139 For Jenny to be 18% BF she should weigh 139 lbs. So when she says she needs to lose 20 lbs I say NO! Jenny needs to drop 11 lbs. Suzie is 230lbs with a BF% at 28%. She is 38 and knows that 20% is excellent for a woman her age and decides to shoot for it. Here we go! RBW=165.6/(1-0.2) RBW=165.6/0.8 RBW=207 Suzie can lose 23 lbs and be looking good feeling fine. Can you picture Jenny and Suzie? Unless you've been in the fitness world for a while, probably not. We don't know how tall either of them are. We don't know if they can bench press 135lbs or if they have never done a bench press in their lives. Let's change this up a smidge. Suzie still weighs 230lbs, but she hasn't engaged in exercise in quite some time. Her BF% is 33%. She still hopes for 20% BF, so let's see how this works. RBW=154.1/(1-0.2) RBW=154.1/0.8 RBW=192.6 Hold up. So why did her RBW change? Look at it. Though the weight was the same, the BF% wasn't. At 33% BF, there is much less LBM. Suzie has no muscle. Now instead of losing 23lbs, she needs to lose 37.4lbs!! Why present this to the public world of the three of my readers? I think we focus all too much on the numbers. We see the scale move or stay and we just can't figure it out. We struggle to see it and hope for the best. It messes with our minds. However, when we take into account how much muscle have, how tall we are, or whatever our situation is, we can accept our bodies for the strong, beautiful, life giving, care taking bodies they are.
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May 2023
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