How Measure Body Fat Percentage Accurately - Iron Paradise Fitness
How to measure body fat percentage accurately article

If you want to know how to measure body fat percentage accurately then you’ll want to read this article.

Read on to discover 6 ways to measure body fat percentage accurately and the pros and cons of each one. 

To shift your body fat you must first know your body fat. Now I don’t mean you should get to know your body fat on first name terms.  This isn’t some form of new age approach where you give your body fat a name like Sophie and spend time talking to it and politely asking her to leave.

No.  This is about establishing your start point.  Your body fat percentage.  If you know where you are and where you want to get to, the process gets that bit easier.

Fail to get step one right and your fitness journey could be a path of long, protracted turmoil and stagnation.  And we don’t want that to happen so let’s get you off on the right foot.

In this article we’ll be getting to know all about Sophie, sorry, your body fat percentage.  What it is, what’s a good amount to aim for, why you need to measure it, and how the hell you measure body fat accurately.

Knowing your body fat percentage isn’t 100% critical to a successful fitness programme, but it can be useful. And this is why I personally won’t start a client programme without first understanding this piece of information.

So get ready to say your goodbyes to Sophie.  The bitch is gonna be packing her bags and getting ready to leave real soon.

What is body fat percentage?

Your body fat percentage is simply your amount of body fat in relation to everything else that makes up your body.  That includes your muscle, bones, tendons, internal organs, and so on.

So if you weigh 80kg and have a body fat percentage of 10% then your fat weighs 8kg, and everything else is 72kg.  Got it?

Good.

It’s also worth noting at this point that men and women are different.  No shit I hear you say.  Not only are men from Mars and women from Venus, but the composition of our bodies is markedly different too.

The fairer of the sexes generally have a higher body fat percentage, due to the need to cater (and by that I don’t mean prepare lots of food) for child birth and other womanly things.  This excerpt from humankinetics.com sums it up nicely, (or at least better than my bumbling prose)

The reason for this difference is that women at some point in their lives may nourish a fetus and then a baby from their own reserves, so women have to stock energy in the form of fat in anticipation of future pregnancies (and must stock even more energy during the last two trimesters of pregnancy).

Sadly women lucked out in the lean muscle department as well.  Your start point for lean tissue is far lower than men due to the variances in hormones.  While each individual muscle fibre has similar strength levels regardless of sex, men have far more as a result of much higher levels of testosterone, which is one of the main reasons we have a greater propensity for muscle growth.

What does this mean in the real world?

Well, if you pick up a bodybuilding magazine and check out the pro bodybuilders.  You know the ones, huge, cartoon-like muscles, bulging veins and skin so thin you can almost see their internal organs like a new-born fish.

These guys are hovering anywhere between 3-5% body fat in these pics (never forget that they are only able to get this low through the use of drugs).  A female bodybuilder of the same condition will more likely have a body fat percentage of 8-9%.  That’s already seriously low, but any less and there’d be a risk of health problems (especially if it was attempted to be sustained).

If you wanted a slightly more ‘normal person’ comparison then at around 10% a man is going to be looking pretty damn athletic.  There’ll be a six pack and if he’s been working out properly there should also be a good degree of muscle and definition on display.  A woman that looks equally fit could have a body fat percentage that was around double the man’s, somewhere in the region of 18-20%.

Now you know what body fat is and what the differences are between men and woman.  How do you decide what body fat percentage to aim for?

What body fat percentage is right for you?

There’s no one single right answer for this as it all depends on what your goal is and how much you’re willing to sacrifice to get there.

Want to get to 6% body fat?  Well, this is about the natural limit for a natural male.  To get to that level of body fat you’ll need to make sure your calories and macros are on point day in day out, your training is optimal and frequent enough, and you’ll also need to be doing a level of cardio.  It takes a lot of dedication to get to this level of conditioning and it’s not something you can half ass.

So if you think 6% might not be for you, what should you be aiming for?  A good place for us to start is the general recommendations from health professionals.  The table below is the rough categories and body fat percentages applicable to men.

Essential Fat

Athletes

Fitness

Acceptable

Obese

2% – 5%

6% – 13%

14% – 17%

18% – 24%

25% and more

As we covered earlier, body fat levels for women are different to men and as such so are the targets.  Here’s the same table but for women.

Essential Fat

Athletes

Fitness

Acceptable

Obese

10% – 13%

14% – 20%

21% – 24%

25% – 31%

32% and more

What Does All That Look Like?

Maybe numbers on a page don’t mean that much to you still and you have that celebrity body that you want to try and emulate.  Brad Pitt from his Fight Club days, Tom Hardy as Bane, or maybe Hugh Jackman in Wolverine.  All physiques that I’m sure men all over the world crave to look like.  And I’m sure there’s an equal amount of women that want you to look like that too!

Let’s stick with the Wolverine himself.  If you want to look like this, then you are talking about a body fat in the range of 6-8% (that excludes the Admantium too).  There’s lots of information online about the Wolverine workout, but no official body fat percentage data. But that’s my best guess based on the visibility of his abs, obliques and overall vascularity.

He looks pretty damn awesome, I think you’ll agree.  And a similar look is achievable naturally with a shit ton of hard work.

hugh jackman wolverine measure body fat percentage

If we then take a look at big, bad, Bane from Batman (Mr. Tom Hardy) we can see evidence of a muscular physique with a much higher body fat percentage.

tom hardy bane measure body fat percentage

You can clearly see from the pic that the dude has been hitting the weights hard.  His chest, shoulders, arms, and traps have a good degree of muscularity.  However, it’s in the ab region where the greatest indications of body fat percentage are.  There is an obvious noticeable difference between Batman’s enemy and the Wolverine.

You can make out the very faintest of definition lines in Bane’s abs, which says to me he’s in the high teens for body fat.  It could obviously be a poorly time snap when he was breathing out, but on face value that’s where I’d place him.

Now you know a little more about what different body fat percentages look like you should start to be able to formulate a clear target in your mind of the body image you want to get to.

This is a great help both for yourself, and someone like me as a coach.  It helps shape your programme and also helps set a realistic timeframe to achieve your goal in.  If your’re starting out at 18% or so like Bane and want to get in the single figure range of our friend the Wolverine then with consistent training and diet adherence that could be achieved in c.16-20 weeks.

The next thing you need to do is establish your base starting point.  This is crucial as it’s going to help dictate your calorie intake.  Get this bit wrong and those 16 weeks could turn into a lifetime.

Time to pay attention.

How to Measure Body Fat Percentage Accurately

You can measure body fat percentage in a number of ways.  Some are expensive and require an expert to help you out.  Others are much cheaper and can be done at home.  All have margins of error. And all have their pros and cons.

I’ve listed below the 5 that I see most commonly talked about.  3 of which I’ve personally used.  The other two I haven’t got any personal experience of, but I have looked into the research around them for the purposes of the article.

1. Hydrostatic Weighing and the Bod Pod

Hydrostatic weighing is considered by many to be the ‘Gold Standard’ when it comes to body fat percentage measurements.  To explain what it is and how it works we need to take a little trip back to your early physics lessons as a teenager and talk about the Archimedes Principle.

Can’t remember what that was all about?  Never fear, I’m here to try and explain it as simply as possible (or at least reference a website that explains it far better than I ever could).  Here’s an excerpt from shmoop.com that explains all.

An object submerged in a fluid displaces an amount of fluid equal to the object’s volume, and the displaced fluid pushes upwards on the object. This is buoyant force. The upward push by the fluid equals the weight of the displaced fluid itself.

archimedes principles measure body fat percentage

 

How Does It Work?

The concept of Hydrostatic Weighing uses the Archimedes principle as the base method for calculating your body fat percentage.  How does it do this?  Muscle and bone are more dense in water.  Therefore, if you’re a regular gym goer with a good amount of muscle, let’s say like our friend Wolverine, then your fat free mass is going to be high, which will weigh more in water and result in a lower body fat percentage reading.

Flip that around a look at someone with a low amount of muscle and fat free mass and you’ll find they are lighter in water, because fat floats.  This will result in a higher body fat percentage reading.

Once the variables have been measured then calculations are made that determine your overall body fat percentage.

The process has a declared error rate of 1-2%.  However, there’s more anecdotal evidence to suggest this could be higher as water temperature can have an impact (as it can effect the density of the water), as can whether or not the subject is suffering from bone conditions affecting bone density, such as osteoporosis.

What Are The Drawbacks?

The major disadvantage is the equipment needed to carry out the process.  The equipment is one usually found at select universities and research centres.  It’s not like this is the type of equipment you can knock up in your back garden.  This is some high-tech and expensive stuff.  Getting access to the use the equipment isn’t exactly easy, but if you do want to explore it, a quick Google search is your best option.

The Bod Pod uses a similar approach to Hydrostatic Weighing whereby the same principles are followed, but using air instead of water.  It again has an advertised error rate of  1-2%.

I did a quick scan through Google of a couple of places offering the service and you can get a 30 minute session for around £49.  To me, that’s a bit expensive if you are going to want to get your measurements on a regular basis to track progress.

2. Dexa Scan

The DEXA (Dual Energy X-ray Absorptiometry) is a scan using a specific piece of X-ray equipment. The machine hovers over your body taking the necessary readings from all the major points on your body, including arms, legs, and trunk.  The process can all be done in 20 minutes with a report in your hand as you walk out the door.

You’ll get an accurate measurement of body fat, lean tissue and bone. This means you’ll have your base starting point. And from here it’s a case of adjusting calorie requirements.

What does it cost?  

For a 20 min scan and report you can expect to pay around £140.  Again, like with hydrostatic weighing, it’s pretty expensive, although it does have the advantage of being pretty accurate with a reported error rate of 1-2%.

Is it really that accurate?

Some would say not.  This study by the University of Cambridge suggests that DEXA can’t be considered the ‘gold standard’ of body composition measurements due to variations in bone and soft tissue values.

The accuracy of DEXA measurements, however, can be problematic. Marked systematic differences in bone and soft tissue values are found between the three commercial systems due to differences in calibration, bone edge detection, and other factors. In addition, differences in reference data provided by each manufacturer can lead to an individual appearing normal on one machine but at risk of osteoporosis on another.

Overall, the DEXA scan is one of the more accurate forms of body composition measurement, but it isn’t infallible.  The cost and inconvenience factor makes it an unattractive option for me.

3. Calipers

This is where the old phrase ‘pinch an inch’ gets used.  These pincer-like implements have been used for decades to estimate body fat percentages.  You can pick up an adequate pair for less than £10 which will more than do the job you need them to do.  Save your money and leave the expensive version for the professionals.

These are the set I’ve got…

Body fat calipers measure body fat percentage

They also came with a tape measure at the time, which is handy if you want to go even further with your initial measurements (which I recommend).  It always nice to know how much you’ve increased the size of your guns by after all those gym sessions.  The fact your shirts no longer fit and it hurts to bend your arm is a good sign you’ve put on some mass, but a measurement will also make it more scientific.

So calipers are pretty good and have their advantages.  They are relatively cheap and can be used at home.

How Accurate Are They?

However (there’s always a but), measuring body fat percentage with calipers is a skill that takes time and practice to perfect.  You need to make sure you’re pinching the right amount of skin in the right areas to get a consistent reading.  You can grossly over or under estimate your fat percentage, just by pinching the wrong bit of your belly.

Want to know how to measure body fat correctly?  Check this video out from Mike Matthews at muscleforlife.com

I also don’t think they’re great if you’re carrying quite a bit of body fat (say 20%+ for a guy).  It can be difficult to get a consistent reading, so I wouldn’t recommend this option if you fit that description.

4. Skulpt

If you’ve never heard of or seen one before, the Skulpt is a handheld device that you position on various points of your body.  The device then calculates both your body fat percentage and your muscle quality.

skulpt measure body fat percentage

How does it work?

The device has sensors of the back that you spray with water before placing it on each muscle.  You link the device to a smartphone app via bluetooth and select either the quick scan or full body scan option.  The app then tells you where to position on the device and away you go.

The quick scan measure your tricep, abs, and quads, whereas the full body covers pretty much everything, including both left and right sides,front and back.

skulpt tracker measure body fat percentage

skulpt tracker 2 measure body fat percentage

I used the device for about a month to carry out my experiment.  Body weight remained fairly consistent throughout the period. And this allowed for an reasonably good assessment of accuracy.

At the time of starting the tests, I estimated I was between 11-12% body fat, just from how I looked in the mirror.  The average reading from the Skulpt was 12.11%.

Here’s how my weight and body fat tracked over the trial period.

skulpt weight tracker measure body fat percentage

skulpt tracker measure body fat percentage

There are significant fluctuations day to day, which I would recommend you remove from your analysis.

My recommendation would be to take readings daily across the week, remove any outliers, and then average out the results.  Adjusting your calories and macros from there should be pretty accurate.

There is a declared error rate of 2-3% which reduces the absolute accuracy, but at £90 it becomes good value for money if you intend to use it a lot.

5. Impedance

Impedance machines are those handheld devices that you see in a lot of gyms.  You know the ones I mean.  Two metal handles they tell you to grip firmly.

Basically, what’s happening here is that a tiny electric current is being passed through your body.  The current flows through fat and muscle at varying rates therefore allowing the machine to measure body fat percentage.

However, I’m not intending to write a lot about these machines as the ones you’ll be able to pick up from your local pharmacy or the ones in gyms are incredibly inaccurate.  So much so that I won’t waste more of your time by reading about them.

Just steer clear!

6. The Mirror

It sounds basic (and it is).  It sounds low tech (and it is).  And it sounds cheap (and it is).  Looking at yourself in the mirror is a great way of estimating your body fat percentage.  It’s the method I used when I first started and it’s the method I use with all my online coaching clients.

So how does it work?  You obviously can’t just look in the mirror and pick an number.  That’s not going to work.

What you need to do is Google the phrase ‘Body Fat Comparison Chart’.  This will pull back a number of images of male and female physiques with associated body fat percentages.  All you need to do is match yourself up to the image that most represent you own look and hey presto you have your estimated body fat percentage.

 

 

For dudes, those well-defined abs start to come in around 10% and for women around 17% and below.  So if you haven’t quite got that look yet, you need to estimate your fat a little higher.

I would always recommend getting some external opinions as well.  We often have the natural tendency to think we’re slimmer than we actually are. So get someone who you trust will give you an open and honest view.

Staring at yourself in the mirror and comparing yourself to pictures on the internet might not be that scientific, but with a bit of practice you can get it pretty much spot on.  And save yourself a whole heap of cash in the meantime.

How Should You Measure Body Fat Percentage Accurately?

I would recommend you use a blend of some of the options I’ve talked through above.  If you haven’t got abs yet, then I’d recommend using a visual check in the mirror. It’s simple, quick and effective.

If you’re abs are showing through, take the time to learn how to use calipers for greater accuracy.  They’re still inexpensive and you can get a greater degree of accuracy. And that’s important if you’re trying to get down to a much lower level of body fat.

The jury is still out on the Skulpt.  It might prove to be a very accurate way of measuring, but the jury is still out.  However, you can give it a go and see what you think.

I would honestly leave the more expensive measurements alone.  It’s simply not worth the expense an the hassle.  If you’re totally shredded and looking for those last few marginal gains it might be a good choice.  But for us mere mortals it seems like the hassle outweighs the benefit.

So there you have it your complete can to getting to know your body fat.  Now comes the difficult bit of getting it to f**k off (sorry for swearing Mum), but that’s for another article.

 

Need help putting that total training and nutrition plan together?

Once you’ve measured your body fat percentage accurately it’s important to have a well-structured training and nutrition plan in place. This will make all the difference in determining whether or not you’ll achieve your goals.

Ultimately, I want to help you achieve your goals.

There are no miracle solutions out there.  But the combination of hard work and the right guidance is the most effective way of getting great results.

If you’re struggling to make sense of it all.  And I don’t mean just body fat.  I get it.

I was where you are right now.  Confused by all the conflicting information and not really knowing if I was doing things right or not.  So if that’s you, why not grab yourself a free copy of my nutrition ebook, ‘7 Steps To Correct Your Nutrition Plan’.

Setting up that programme from day 1 is going to be crucial to your success.  Don’t spend any more time spinning your wheels or heading in the wrong direction.  Grab the eBook and get on the right track now.

Simon

 

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