Muscle for Life with Mike Matthews - How to Calculate Your Body Fat Percentage Easily & Accurately
Episode Date: June 3, 2019In this podcast, I want to share what I've learned on calculating body fat percentage, including ... What “body fat percentage” means. The pros and cons of popular ways of calculating body fat pe...rcentage. How to determine your body fat percentage with a fair amount of accuracy. Why obsessing over body fat percentage is counterproductive (and what to do instead). And more. Let's get started. 5:37 - What is body fat percentage? 6:56 - What’s the difference between body fat percentage and body mass index? 8:56 - Can you determine your body fat percentage based on your body mass index? 11:09 - What is a healthy body fat percentage for men and women? 23:09 - What are the different ways to measure body fat percentage and how accurate are they? 37:07 - How do you calculate body fat percentage? 44:01 - What is the best way to reduce body fat percentage? Want to get my best advice on how to gain muscle and strength and lose fat faster? Sign up for my free newsletter! Click here: https://www.muscleforlife.com/signup/
Transcript
Discussion (0)
Hello, hello, hello.
I am Mike Matthews and welcome to another episode of the Muscle for Life podcast.
This one is going to be all about body fat percentage, which I thought I had spoken about
previously and was surprised to learn that I had not done an episode on measuring body
fat percentage yet.
So here it is. And me thinks it will be one
of the more popular episodes that I've done in a bit because measuring or estimating body fat
percentage can be pretty confusing. My first experience with this was several years ago when
I got very lean for a photo shoot, somewhere around what I
would have thought was six or 7% body fat. Competitors step on stage around four to 5%.
I wasn't that lean, but I was getting there. I had ab veins. I couldn't pinch any fat really
anywhere on my body and everything just looked sharp and defined. And so I tried measuring
my body fat and my score was 11%. And it's not that I really cared about the number. Ultimately,
what you see in the mirror is what matters. And I looked great. I looked about as great as I can
possibly look. So if that was 11%,
then it was 11%. But it still didn't quite make sense because again, I looked like I could have
stepped on stage maybe as a physique athlete, for example, not bodybuilder shredded, not shredded
glutes shredded, but very, very lean. And if that was 11% and to get bodybuilder lean, I would need to lose, let's say another 6%
body fat, or let's see, cause I was weighing about, I think 185 at the time. So that means
that to get body builder lean, I would have to lose another 11 pounds of fat, 11 pounds. I mean,
imagine a pound of fat is like a solid handful of fat.
And looking at my body, I literally had no idea where all that would come from. Again,
I was assuming that I was maybe five pounds of fat away from bodybuilder lean. And the way that I
came to that measurement was the standard bodybuilder approved multiple point caliper test,
which we did several times just to confirm each of the measurements. And so according to that
measurement, I was still carrying around 20 pounds of fat on my body, total, total body fat,
20 pounds. And so it was confusing because where was all this phantom fat
hiding? I couldn't pinch anything more than like skin anywhere on my body. And also considering
what it took to get that lean, if that was really 11%, I guess even 7%, let alone 5% would have
just been impossible. I had dieted for a couple months and was feeling
okay, but it was definitely starting to take its toll in terms of energy levels, sleep, sex drive,
workouts, and so forth. And so I then set out to learn what was really going on. And in this
podcast, I'm going to share what I've learned, including what body fat percentage is, the pros and cons of various popular ways of calculating body fat
percentage, how to determine your body fat percentage with a fair amount of accuracy,
why obsessing over body fat percentage is counterproductive and what you should do instead,
body fat percentage is counterproductive and what you should do instead and more.
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at least let's get to the show. All right. So let's start with what is body fat percentage? Well, your body fat percentage
is exactly that. It is the percentage of your body weight that is fat. So for example, if you weigh
150 pounds and you have 15 pounds of fat on your body, your body fat percentage is 10%, right? 15
divided by 150. And this means that your body fat percentage is a moving target because it
changes when you gain fat, it changes when you lose fat, and also when you gain and lose muscle.
So for instance, if you used proper diet and weightlifting to increase your weight from,
let's say, 150 to 170 pounds with just five pounds of additional fat gain, your new body fat percentage would be about 12%
because now you have 20 pounds of fat divided into 170 pounds of total body weight. And then
let's say that you stopped lifting for a year or so and lost 10 pounds of muscle, but no fat,
your new body fat percentage would still be around 12% because you have 20 pounds
of fat divided into 160 pounds of body weight. So the point is your body fat percentage ebbs and
flows as you change your body composition. Okay, so next I want to talk about body fat percentage
versus BMI because I often get asked about this and many people mix these
things up, but they are completely different. So BMI stands for body mass index, and it is a
numeric expression of the relationship between your height and your weight. Now you calculate
your BMI by dividing your weight in kilograms by your height in meters squared. So for example,
my BMI when I was 185 pounds and super lean was about 25. Now, according to BMI data,
that would put me in the overweight category because BMI values are correlated with different body weight statuses. So underweight
would be a BMI under 18.5. Normal weight is 18.5 to 24.9 and overweight 25 to 29.9 and obesity would
be 30 and above. So according to that, I was borderline overweight. I was just in the beginning phase of
being overweight despite being pretty shredded, which of course is silly. And that is the rub
with BMI. It is useful for analyzing broad populations and also sedentary people or people
who maybe exercise, but who don't train their muscles at all. But it is not very useful for those of us into fitness,
and especially into any type of resistance training. Because of course, muscle weight
is not distinguished between body fat weight. And as I carry around a lot more muscle than the
average person, about probably 40, 45 pounds more than the average person. This bumps up my BMI quite a bit, despite having a low body fat percentage, very low at the time of when I was
looking into all this. And even now, currently I'm probably around 11% or so, which is still
quite a bit lower than the average person. Another thing I am often asked about is determining body
fat percentage based on BMI. Can you do that? And the answer is
no. Most people can't because as BMI is solely based on your height and weight, it does not
take into account how much of that weight is fat versus muscle. And what that means is BMI can be
high for different reasons. On one hand, it can be high because like me, you are a pretty muscular person and you're
also fairly lean. On the other hand, it can be high because of the exact opposite. It could be
high because the person has a low amount of muscle or maybe even an average amount of muscle, but a
lot of body fat. That said, there is one situation where you can use BMI to at least roughly estimate someone's body
fat percentage. And that is in overweight people with normal levels of muscle mass. So people who
don't train their muscles regularly. And in that case, BMI is actually often similar to body fat
percentage. So for example, a guy who's let's say 5'10", 200 pounds, 30% body fat would probably have a BMI of about 30.
And likewise, a 5'4", 160-pound woman at 40% body fat would probably have a BMI of about 40.
This correlation disappears, though, when you start looking at lean people. So for example,
my body fat percentage is typically around 10%, give or take a percent or
two, but I would have to starve myself to a life-threatening 76 pounds or just a dead 76
pounds to get a BMI of 10 or 11 or 12. This relationship also disappears with people with
above average muscularity. My BMI was 25
when I was very lean, but my body fat percentage was less than a third of that. And this is why I
never recommend that people use BMI to estimate body fat percentage, even if it kind of sort of
works in some situations. Even then, there are better ways to estimate body fat percentage.
Alrighty, so that's it for BMI and body fat percentage. And next on my list of things to
discuss is what is a healthy body fat percentage for men and women? Because as much as it is
generally despised, body fat is much more than a layer of ugly, unwanted, greasy flesh to be
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Body fat actually plays many vital roles in the body, including protecting organs from damage,
maintaining body temperature, producing various hormones like leptin and other chemicals and much more. And that's why there's a limit to how lean you can get before your health starts to
decline. What is that limit though? Well, first let's start with some classifications of body
fat percentage ranges. So in men, the essential range is four to 6%. The athlete range is 7% to 10%. The fit range is 11% to 16%. The normal range is 17% to 25%.
And the overweight, eventually obese range is 26% and above. And in women, it looks like this.
The essential range is 10% to 12%. The athlete range is 13% 20 percent. The fit range is 21 to 24 percent. Normal
is 25 to 31 percent. And overweight slash obese is 32 percent and above. And in case you are
wondering, the additional fat that women carry in their breasts, hips, thighs, and butts accounts for their generally higher body fat percentages
and higher ranges. Now, studies show that the absolute leanest men can get under any circumstances
is about 4% to 5% body fat. You try to go beneath that, you die. And the leanest women can get is
about 10% to 12% body fat. That's why it's called that essential body fat range. And the leanest women can get is about 10 to 12% body fat. That's why it's called that
essential body fat range. And the reason for this is once you get this lean, all that's left
is small amounts of body fat stored in nerve cells, brain tissue joints, and the pads of your
hands and palms of your feet, and covering major organs like the heart and intestines. This is the body fat that is required
to stay alive. So when someone hits this essential body fat range, which it has been done,
and there are plenty of examples on the internet of beyond shredded, like shredded to the bone,
almost literally bodybuilders out there who have done it. And when they do this,
they are taking their lives into their hands. Their lives are literally on the line because
if they keep losing fat, eventually their heart can stop or they can fall into a coma, which is
why actually your body starts to protect itself by beginning to break down muscle tissue and then internal organs for
energy instead of burning the last bits of essential body fat. And this is why studies
show that people who die of starvation still have most of their essential body fat. Now,
you might be scratching your head at this point because of some of the sweet body fat brags that you have
seen on social media or maybe heard in the gym. For example, I've heard guys in the gym in the
locker room say that they got down to 2% body fat for their competition. And I've heard women claim
five or 6%. Now, as you know, this is physiologically impossible. How can these people be so off though
in their estimations? Well, usually it's just willful ignorance or outright lying, but sometimes
it's because the methods they use to measure their body fat percentage are wildly inaccurate,
and especially in people who are lean. And we'll talk more about that in a minute.
And just for the sake of reference here, if you want to see what four or 5% body fat really looks
like, search for a dude named Helmut Strebel, H-E-L-M-U-T-S-T-E-B-L. And you will find pictures of the most shredded dude you've probably ever seen in your
life. That's what four or 5% body fat looks like on a guy. Now, if you want to see what 10-ish
percent body fat really looks like on a woman, search for it's a Daily Mail article, the British
tabloid, I think it is. And the title is Ripped Female Bodybuilder
with an Incredible 0% Body Fat Shows Off Her Trim Physique But Sparks Debate Over Whether
She's Healthy. Now, of course, she doesn't have 0% body fat, but she is absolutely shredded.
And that's what 10% or so looks like on a woman. And my advice to you here is, even if you
think it looks cool, unless you are a competitive bodybuilder and unless you know exactly what
you're doing with your body and why, do not ever try to get this lean. Your hormones are going to
go haywire. Your organs can fail. And even when you avoid disaster, the road back to normality can be quite long and bumpy.
There are case studies out there of natural bodybuilders dealing with hormonal abnormalities
a year after competing. Now, I'm sure they made mistakes along the way in terms of their prep and
post-competition, off-season, but still, it's pretty impressive how much getting and staying
really lean can mess up your body. Now, fortunately, you are probably like most people and
you'd never want to get that lean. Instead, you probably just want to be in the lower end of the
athletic range, or maybe even just in the middle of the athletic range, right? So for men, that's 7% to 10%. And
for women, that's 13% to 20%. And this is what most people would consider ripped or shredded.
Most guys are going to be happy really at 10%, honestly. And if they want to get really lean,
they maybe get down to like 8%. And for women, most are happy around 20% if they just have muscle
in the right areas of their bodies. And if they want to be really lean, maybe they take 18% or so. And if you want to see what those body fat percentages
look like for the men, just search for some shirtless pictures of Cristiano Ronaldo. I'm
not sure if I'm pronouncing his first name right, but the famous soccer guy. He is usually around,
most of the pictures I've seen, probably around 7% or 8%. He's very lean.
If you want to see the equivalent for women, probably somewhere around 17% body fat or so, search for Jessica Ennis, E-N-N-I-S.
And you'll find there are a few famous pictures of her holding up the British flag.
And that's what 17% or so looks like on a woman.
And that's what 17% or so looks like on a woman. And in case you're wondering, I'm talking about elite athletes here simply because there's a lot of high quality research on them. This is why we know, for example, that top male athletes in many different sports are usually around 6% to 10% body fat and the females are usually around 13% to 20% or so. And the good news is anyone can look like Ronaldo or Ennis with proper dieting and exercise. It is not pleasant to try to maintain that look for very
long periods of time, unless you are very, very active like an athlete, which allows you to eat
more food and is just better on your body than trying to stay very lean on smaller amounts of food.
But it can be done if you are willing to strictly control your calories. And unfortunately,
that can be hard when you are fighting against your body's natural desire to be fatter, really.
Your body does not want to be 7% or 8% body fat or 16% or 17% if you're a woman. It would much rather be probably
closer to 10% to 15% if you're a man or 20% to 25% if you're a woman. And if you want to learn
more about why, search for the podcast, just search for my feed for Setpoint, and you'll find
an episode that I recorded on this specifically. So while that's the case with the lowest levels of
that athletic range, 7% in men and let's say somewhere around 15% in women, the good news is
you can maintain slightly higher levels of body fat, at least most people can, while still being
able to enjoy life, eat foods that you like. You can't eat whatever you want,
whenever you want, of course, but have good workouts and be healthy. Now, it is not necessary
to be that lean to be healthy. Generally speaking, the health benefits of fat loss drop off around
15% body fat in men and around 20% in women. So you can be more or less just as healthy as a guy at
15% as you can at 10% or even 8%. And the same for women at let's say 25, 20 or 18%. And so the only
real reason to bring your body fat percentage below the fit range into the athletic range or
the athlete range, especially the athletic range or the athlete range,
especially the lower levels of the athlete ranges. It's about vanity really, and just feeling better
about how you look rather than improving your health. And that's okay. I think that's a
perfectly valid reason to do it. In fact, I think everybody should do it at least once because it is
cool. It's not very hard. If you know what you're doing, you just got to stick with it. It's not the
most enjoyable thing. You will have to deal with some hunger and deal with
some cravings probably, but if you know what you're doing, it's going to be pretty smooth sailing.
And especially if you incorporate something like calorie cycling and diet breaks, which you can
learn about either on my podcast here. I recently published an episode on calorie cycling, so you
can search my feed and learn about that. And I don't think I've done an episode on calorie cycling, so you can search my feed and learn
about that. And I don't think I've done an episode on diet breaks yet. Oh no, I did. I recorded
an interview with James Krieger. So if you search for Krieger, K-R-I-E-G-E-R, I believe diet breaks
is probably in the title as well. So you can learn about those things there. So my point is,
if you incorporate calorie cycling and diet breaks into the later phases of the diet, when let's say if you're a guy and
you're at about 10% and now you're going to make that final push to get to 7% or 8%, or if you're
a woman and you're at 20%, you're going to make that final push to get down to the 17%, 18% range,
incorporating calorie cycling and diet breaks can make it even easier and just more enjoyable,
less painful.
And so my point with that is you do it right and you can take a bunch of pictures.
You can enjoy it for a bit.
I wouldn't recommend trying to stay there for extended periods of time, but it is fun.
Now, once your body fat levels rise above the fit range, that's when you start to look
overweight.
And I generally recommend that people do not exceed
that range of body fat because it starts to get unhealthy, it slows down muscle growth,
and it's going to make any later efforts to get lean longer and grueling. When you have
six months of dieting ahead of you, that is a lot more daunting than three months.
All right. So now let's talk about calculating body fat percentage. How do you do it? Well, there are quite a few
ways of doing it and you can get quite a few different results based on what you do. So in
my case, the multiple point caliper test that I was talking about in the beginning of this podcast said I was 11% body fat, but then the handheld device in the gym said I was 8%. And a different method,
a single point caliper said 6%. So what gives? Well, let's go down the list here. Let's talk
about body composition scales and handheld devices first, because they are the simplest
way to measure your body fat percentage.
You step on the scale, you hold the device, you get a number. Now, these instruments use a method
called bioelectrical impedance analysis, BIA, which involves measuring your body's resistance
to a light electrical current. Muscle conducts electricity very well because it is over 70%
water and fat does not because it holds much less water. Thus,
the more resistant the body is to an electrical current, the fatter it must be. That's the logic
behind the method. And it sounds reasonable enough, but there are some serious problems with
BIA. First, electricity takes the path of least resistance. So as the current passes through your body, it will actually avoid
fat stores for tissues that are easier to traverse. So internal tissues will be chosen over
subcutaneous fat, for example. And making matters worse is the fact that two electrode devices like
scales, or at least most scales and handhelds, skip entire portions
of your body. The foot-to-foot scales miss your entire torso and hand-to-hand devices miss the
lower half of your body. And as you can imagine, this corrupts the results. Another problem with
BIA is it uses mathematical equations to turn the raw readings of the devices into body fat percentages.
And these equations can be very flawed.
You see, when a company develops a BIA device, they calibrate it using another imperfect method of measuring body fatness, like hydrostatic weighing.
And there are several steps involved
in this process. So what they do is they measure the body fat of a large group of people with the
control method. So in this case, it would be the hydrostatic weighing. And then they would measure
again with the BIA device. They would compare the readings and then they would develop an equation
to predict BIA results based on
height, weight, gender, and other variables. And this is not a bad approach. It could work
if the control methods readings were accurate, but unfortunately, they are often not. So in other
words, many companies are calibrating their BIA devices to conform to incorrect calculations of body fat percentage. Hydrostatic weighing
is the one that is most frequently used for BIA benchmarking, and studies show that it can be off
by as much as 6%, and that's in an absolute sense, not relative sense, for a number of reasons
relating to ethnicity, body weight, hydration status, and more. And again, if 6% doesn't sound
too bad for you, I'm talking about absolute, not relative. So if someone is actually 10% body fat,
they may register at anywhere from 4% to 16% body fat with hydrostatic weighing.
Another problem with BIA devices is body conditions can dramatically influence readings.
So for example, if you test your body
fat with a BIA device when you are dehydrated, you are going to read abnormally high due to
lower conductivity in the body. If you were to test after eating, you would see the opposite
effect. You would read abnormally low. For example, in one study, being fed reduced readings by 4.2%. Research also
shows that the body is more conductive after exercise. So if you were to test after a workout,
you would get another artificially low reading. And these are some of the reasons why scientists
have said that consumer level BIA devices are just not suitable for accurately estimating body fat
percentage. Now, what about using one of these devices for tracking changes to your body fat
over time? If BIA were at least consistently inaccurate, that might work, right? At least
for determining whether your body fat percentage is going up or down. And sure, but unfortunately, these devices are just
too all over the place for even that. So they have really no good use. All right, let's move on to
body fat calipers and skin fold testing. Now, skin fold testing uses calipers to measure the
thickness of your skin at various points in your body and the measurements are added together and
then fed through a couple of equations that ultimately give you a body fat percentage.
And I think you might see where this can go wrong. Namely, if you pinch too little skin,
you're going to read lower than you are. If you pinch too much skin, you're going to read higher. And then beyond pinching,
there is the problem of bad equations, bad math. So for example, in one study, a team of scientists
at the VA Medical Center in Durham, North Carolina took skin fold measurements of 681 healthy men and
women. And as a control, they also measured everyone's body fat percentage using a far more accurate technique known as the four compartment model, which we will talk more about
in a bit. And what the researchers found is that the skinfold measurements were about as accurate
as the four compartment model for measuring the average body fat percentage of the entire group. But when it came to individuals,
the skin fold measurements were very wrong for many of the participants. In many cases,
the skin fold measurements either over or underestimated body fat percentage by as much
as 10 to 15%. And yes, that's absolute. So a guy at 20% body fat, he might get a reading of 5% body fat,
stage shredded, or 35% body fat obese using the skinfold methods in the study. In another study,
skinfold testing produced measurements that ranged from 5% too low to 3% too high. And another study that was conducted with bodybuilders demonstrated
similar error rates. So the upside to skinfold testing is this. Some methods are more accurate
than others and do lend themselves well to tracking changes to body fat levels over time.
And we'll get to that in a few minutes. Next on my list for
estimating body fat percentages, pictures, and the mirror. And this is the simplest and the most
obvious way to guesstimate your body fat percentage. Most people around a certain body
fat percentage look similar if they have similar amounts of muscle. If they don't, then the same
body fat percentage
can actually look quite a bit different on two different physiques. So for example, a 160-pound
guy at 10% body fat has 16 pounds of fat, whereas a 190-pound guy at 10% has only three pounds
more fat, but quite a bit more muscle, giving him a very, very different look.
Now, if you are still listening to this, chances are you are into working out and you probably have
a bit more muscle than the average guy or gal. So if you'd like to see a chart that would allow you
to quickly estimate your body fat percentage, just search for Legion Athletics body fat percentage,
and you'll find an article that I wrote that this podcast is based on. And there is a chart in there
for guys and for women that shows everything from four to 5% to 35 to 40% for men and 12 to 14% to 50% plus for women. And if you go check out those charts, you'll see that the
coveted six-pack emerges around 10% body fat in men and about 20% in women. And abs slash core
vascularity starts to become visible around 8% in men. Genetics do play a role here. Some people are just naturally
vascular and some people are not. I am not, for example. Abvascularity for me does not really
start to show until probably 6% or 7%. But in women, abvascularity starts to show around 15%
in most women, maybe a little bit lower than that. And the kind of carved out of stone
look is about 6% in men and 11 or 12% in women. All right, let's move on and talk about the next
method of estimating body fat. And that is dual energy x-ray absorptiometry or DEXA. And this
is a technology that uses a full body x-ray to help calculate your body fat
percentage. And the scientific basis of this method is that fat and fat-free mass absorb
x-ray energy differently, which then allows each of these elements to be isolated and measured.
And that sounds like it should be very accurate, right? And most people
do indeed think that DEXA readings are unerring. If the DEXA says that the dude is 7%, he is 7%,
end of story. But research shows otherwise. Ironically, DEXA can be just as inaccurate as
any of the other methods that we've discussed so far. For example, in two studies, the individual
error rates using DEXA were as high as 4%. And again, that's in an absolute. So somebody at 10%
could read at 6% or 14%. In another study, the DEXA was off by 8 to 10%. And that helps explain
why many bodybuilders in contest shape have been a bit
perplexed by their DEXA readings of anywhere from six to 10 percent body fat. You know, when you are
a guy with dick skin everywhere on your body, as the bodybuilders like to say, literally there's no
fat left. You just pull skin off of your muscles and you go and DEXA at 10%, you got to wonder, right?
And there are several reasons for DEXA's fallibility. The results can differ between
machines, both from the same and different manufacturers. The accuracy is affected by
gender, body size, body fatness, and even disease state. Different machines use different algorithms to interpret the
raw data from the body scans, and some are just better than others. Even the type of x-ray used,
fan versus pencil beam, influences the accuracy of the test. And so does how hydrated you are.
That can greatly affect the results. So the bottom line here is, as with the other methods we've discussed so far, like BIA and skin fold testing, Dexascan can give you an accurate calculation of your body fat percentage, but it can air instead of water. So what you do is you sit in a seated chamber and
then sensors measure the amount of air that your body displaces. And then mathematical formulas
are used to translate the readings into body composition statistics. Now we already know
how inaccurate hydrostatic weighing can be. And unfortunately, research shows that the BOD pod seems to be even
worse. Its accuracy is affected by more variables like facial hair, moisture, body temperature,
and even the tightness of the clothing that you're wearing when you are sitting inside the device.
So for example, in one study, BOD pod readings were off by as much as 15%.
And in other studies, error rates of 5% to 6% were seen.
And that research helped explain for me some of the rather shocking bod pod readings that I've seen working with others.
I've come across dozens of people in my travels whose bod pod measurements were easily double their actual body fat percentages
because you don't need more than eyeballs to know that a dude around 10% is not around 20%.
All right, so those are the most popular methods that people use to calculate or estimate body fat percentages. And obviously they all have serious flaws. So
how do we do it then? How do we calculate our body fat percentage? Now, I mentioned something
earlier, which is this four compartment analysis. And this is how scientists were able to determine
the error rates of the various testing methods that we've gone over.
They checked BIA, dexabod pod, hydrostatic, and skinfold results against the four-compartment
analysis, which is the gold standard of body fat calculation. And this method involves using
several testing methods to piece by piece separate body weight into four categories,
bone, water, muscle tissue, and fat mass. So for example, hydrostatic weighing is used to measure
body density, deuterium dilution is used to measure total body water, and DEXA is used to measure
total bone mass. And then the data that's collected from
each of those tests is manipulated with various equations and the result is a consistently
accurate measurement of body fat percentage. Now, this is nice to know, but it's not very useful
for most of us because it requires a team of scientists. Fortunately, however, there is a
method of calculating and tracking body fat percentage that I feel is fairly accurate and
consistent enough to warrant the time and attention. And this is how I do it myself.
So what I do when I want to keep close tabs on my body fat percentage, so let's say when I'm
cutting or when I'm lean bulking is I use calipers, a
scale, a measuring tape, and the mirror. So let's go over these things, not necessarily in that
order. Let's talk about the scale first. So what I do is I weigh myself every day, and then I
calculate an average weight every seven to 10 days. And the reason I do it this way is your
weight can fluctuate from day to day due to things that you can't see or even necessarily
control like water retention, glycogen storage, and bowel movements. And this is why you don't
want to put too much stock in daily weight measurements. Your weekly weight averages are
much more useful because they give you a much truer picture of what is actually happening with your body weight.
Because if your seven to 10 day averages are going up over time, you are gaining weight.
Some people also do even bi-weekly. They like to average every other week as well. But anyways,
if the average is going up, you're gaining weight. If the average is going down, you're losing weight, regardless of what the day-to-day is doing. So weigh yourself every day, first thing in the
morning after the bathroom
and before any food or water, record your daily weights and then take an average every seven to
10 or maybe even 14 days. And of course you do that by just summing the daily weights and then
dividing by the number of days and then watch those averages. And then you won't need to fret
over temporary movements up or down in your body weight. All right, let's talk about caliper
measurements and taking bi-weekly caliper measurements. So generally speaking, if your
skin is getting thicker over time, you are gaining fat. And if it's getting thinner,
you are losing fat because of course, most of the fat that we are gaining and losing
is subcutaneous fat. It is the fat underneath the skin. And this is why caliper readings can be
useful despite being not very reliable for determining body fat percentage. Now, I've tried
many calipers and skinfold testing methods. And the one that I've found best that I have liked the
most is from a company called AccuMeasure, A-C-C-U measure. And if you go on Amazon,
you can find something called the AccuMeasure Fitness 3000 body fat caliper. That's the
caliper I like to use. I'm not getting paid to recommend that, but that is just the one that I
like and use. And there are two reasons why I like it. One is it's a simple one site testing
method, which means there are less ways to screw it up. And two, it's actually surprisingly accurate. Again, I don't recommend only going off of this reading,
but I've used it quite a bit myself and I've worked with a lot of people using it, and I rarely see
flagrant misestimations. It usually seems to be accurate to within a couple percent. And in terms of how to use it, you can just follow
the instructions. Again, it's a one site method, so it's pretty easy to use. And I used to personally,
and I used to recommend doing weekly caliper measurements to coincide with weekly waist
measurements and progress pictures. But I stopped doing that because skin fold thickness tends to change slower than other
measurements. So typically you'll only notice maybe a millimeter or two of difference from
one week to the next, which can be easily missed by just placing the calipers in a slightly
different spot or not pressing down as hard as you did last time or whatever. Another reason why I
started doing bi-weekly and not weekly is taking
caliper measurements does take longer than taking waist measurements and progress pictures. And
most people to kind of just get tired of doing it every week. And especially when the changes
are so subtle and it's not vital, you could take no caliper measurements and you'd be okay.
But I figured I'd mention it because a lot of people do like to do calipers.
So there it is. Bi-weekly, that gives you enough time to see more significant and less error-prone
changes in your skin fold thickness. Let's talk about waist now. I recommend taking weekly waist
measurements when you want to keep an eye on your body fat percentage because the size of your waist measured at the
navel is a reliable indicator of fat gain or fat loss. An ever-expanding waist indicates fat gain,
an ever-shrinking one indicates fat loss. And that's why it is a good measurement to keep an
eye on. And of course, all you need is a simple measuring tape. Lastly, we have pictures.
I like to take weekly pictures. And if you're like most of us, gym goers, the point of all of this,
for the most part, is what you see in the mirror. And I'm just as guilty as everybody else. And the
problem though is when you look at yourself every day in the mirror, you can get discouraged because you are not seeing the gradual improvements.
If you take weekly front side and back pictures, though, in good front on lighting in the same
position, same spot every time, of course, it helps greatly with seeing your progress
and staying motivated.
So that's it.
That's how I recommend keeping an eye
on your body fat percentage and estimating it. You can use the charts in the article and just
compare to what you see in the mirror. You can use the caliper. That should probably also,
the one that I recommended should also give you a fairly accurate estimate. And then you just keep
tabs on how things are changing from there. Now I want to, before we wrap up here, talk about
the best way to reduce your body fat percentage, because there are actually two ways to do this.
Of course, if you lose body fat while maintaining muscle mass, your body fat percentage is going to
go down. That's obvious. But a lot of people don't consider that if you increase your muscle mass
while minimizing your fat gain, that also
decreases your body fat percentage. Now, when you run the numbers, though, you quickly see that the
fat loss option is far more effective for reducing your body fat percentage than the muscle gain
one. And the reason why is when you know what you're doing with your diet and your exercise,
you can expect to lose
around, let's say a pound or so of fat per week. It might be a little bit less if you're lean,
wanting to get really lean. It might be a little bit more if you're overweight. When you are lean
bulking though, the best you can hope for after your newbie gains are gone at least is maybe a
half a pound to a pound of muscle per month with about the same amount of fat gain.
And furthermore, that target for muscle gain becomes smaller and smaller as you near your
genetic potential for muscle growth until it finally just becomes vanishingly small.
So for example, let's say that you weigh 150 pounds at 15% body fat. So you're a guy, 150 pounds, 15% body fat, and this
gives you 127.5 pounds of lean mass and 22.5 pounds of fat mass. And then let's say that you
lean bulk successfully for a year and you gain 10 pounds of muscle and 10 pounds of fat, putting you
at 137.5 pounds of lean mass and 32.5 pounds of fat mass for a total body
weight of 170 pounds. If you divide the fat mass by the total body weight, you get about 19%
body fat. And what you have learned then is despite gaining 10 pounds of muscle, which is
very, very good for a year if you're not brand new, with pretty minimal fat gain,
you are still quite a bit fatter than you were before the gaining phase. Now let's see what the
numbers would look like if you decided to reduce your body fat percentage by cutting. So again,
let's say that you weigh 150 pounds and 15% body fat, 127.5 pounds of lean mass, 22.5 pounds of fat mass.
You cut, you lose 10 pounds of fat without losing muscle, which you definitely can do.
You're going to lose some water weight and some glycogen weight, which may register as lean mass,
but you didn't lose any actual muscle tissue. So that brings your body weight down to 140 pounds, and you still have your 127.5 pounds of lean mass and
12.5 pounds now of fat mass, which becomes about 10% body fat. Now, I know the lean mass would be
a little bit less due to water and glycogen depletion, or at least reduction, but I'm just
keeping the number simple to make a point here. And that is that cutting reduced your body fat
percentage by 50%, relatively speaking, of course.
You cut it in half, and it did that in a quarter of the time that it took to build 10 pounds of muscle.
Now, of course, that is not to say that building muscle is not going to improve your physique, of course, but it will not have the same effect on your body fat percentage and your appearance as quickly as losing fat will.
Well, those are all the key things I wanted to cover in today's podcast. So let's just run back
through the highlights. So your body fat percentage is just the percentage of your body weight that is
fat, and it is a better measurement of your overall health, fitness, and body composition than BMI. And it's also useful
for setting weight loss goals. A healthy body fat percentage for men is somewhere between 8% and 16%
body fat. And a healthy body fat percentage for women is something between 16% and 24%.
And I've found after working with thousands and thousands of people over the years that most
men are happiest somewhere around 8 to 12% body fat. And most women are happiest somewhere around
18 to 22% body fat. Yes, you can get a bit leaner, but it's usually not worth the trouble.
It can be fun. You can get some pictures. You can brag. But in the end,
you are probably going to find that you just enjoy life more when you're a little bit fatter.
Now, speaking of bragging, there are many people out there who brag about their supposed super low
body fat levels. But the only way to know your body fat percentage with absolute certainty is to remove all of the
fat from your body and weigh it. And I doubt even the most narcissistic of the bunch are going to
volunteer for that. So with autopsy off the table and four compartment analysis out of reach for
most of us, the bottom line is that body fat calculations themselves aren't just not
as important as how they are changing over time. And this is why I don't bother with inconvenient
and expensive testing methods like DEXA or the BODBOD. You may or may not get an accurate reading,
so why bother? Instead, you can just use your weight, your skin fold results, your waist measurements,
and your pictures to know exactly what is happening with your body.
Hey there, it is Mike again.
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