I'm going to explain the tools I use to measure my clients' skinfolds, body composition and other progress measurements. A few weeks ago, I got a question following on from my ISAK Skinfold Measurements article about the equipment I use. These accurate measurements are vital to track fat loss as well as seeing improvements in muscle mass and overall conditioning.
The basics of body composition - equipment for measuring height and weight
Height and weight are two very simple measurements that are often overlooked when it comes to progress tracking. While individually neither tell you very much, when used in combination with other measurements and factors, height and weight can give important insights into health and body composition.
Bathroom weighing scales
The scales I currently use (for myself, and my clients) are the WW Body Balance Bluetooth Diagnostic Scale WW910A.
I really like these as they are fast, reliable and accurate. They have a bright LED display that gives weight readings in 0.05kg increments. This feature isn't that common among bathroom scales and can give a higher degree of precision with readings.
They have BlueTooth connectivity meaning I can connect them to my iPhone and store data quickly and easily. I don't use this feature with my clients, but for personal use, I think this is great. My own measurements are automatically tracked and saved and I can quickly and easily measure my progress.
These are currently available at Myer, as well as other retailers.
I also have a Seca model (Seca 762 Mechanical Personal Scale) however I don't like this version as much.
Seca are well renowned for producing industry-standard, robust and reliable products.
These scales are definitely well made and sturdy. The problem I find with them thought is the graduation is only in 0.5kg (500g) increments. This may well be fine for your needs, but for tracking potentially small changes in already lean clients, this lack of precision isn't ideal.
I also found the footplate with these scales is an odd shape. As a result, clients with large feet have to take care and angle their feet correctly to remain stable. Finally, these scales are fairly heavy at 3.5kg (7.7lbs). For most, this probably isn't an issue however if you are travelling to different locations, possibly measuring clients in their own home, this can become an important consideration. You might prefer an option that is more lightweight and portable.
Measuring height - stadiometers
So you may or may not be aware that the tool used to measure height is called a stadiometer. Essentially this is just a big vertical ruler. You stand next to it and read the subject's height off the scale.
My current favourite tool is the Seca 213 Portable Stadiometer.
I really like this stadiometer for several reasons. It is portable yet sturdy and reliable. You can dismantle it and all of the parts fit neatly into the base which has its own built-in carrying handle. If you travel to different locations then this feature could prove invaluable. It only takes minutes to assemble or disassemble and is a simple and straightforward process.
The scale is clear, accurate and easy to read. There is a large head plate that slides smoothly up and down. You can adjust this until it just touches the top of the subject's skull and they can step away without any interference to the reading.
Lastly, and perhaps my favourite feature, is you can use this stadiometer on practically any surface
You may or may not be aware, but the surface you stand on can have a big effect on the reliability and accuracy of your measurements. An ideal surface would be something hard and ungiving - like tile or concrete. However many offices and homes have carpet, rugs or other soft coverings. Softer floor coverings, especially more plush options or carpets with thicker piles, have a bit of 'give' in them. This can mean subjects essentially sink into the floor and can affect the readings taken.
That's why when measuring weight using scales, you should always place them on a firm level surface. When measuring height though, it's easy to overlook this point.
The Seca 213 stadiometer overcomes this though as it is a self-contained all-in-one unit. It has its own base built in - a platform for clients to stand on. The height scale directly connects to this base. The scale shows the height from this base plate and not the floor.
Essentially this means that no matter what surface the unit is placed on, height is always measured relative to the base plate. If it's on a deep pile carpet, the base plate sinks into the carpet along with the attached scale by the same distance.
And that's important for accuracy.
Compare this to a stadiometer that only features the height scale, fixed to a wall for example. The subject stands under the scale, on the plush carpet, and effectively sinks into the floor. This may be up to 2-3mm or even more. The height chart fixed to the wall doesn't move, therefore all readings will have a greater margin of error.
Other stadiometers I've used - the S+M Height Measure 2m
In a pinch, this one's ok.
You screw it into the wall above where your clients stand. Once they are in position, you slide the gauge down the wall until it reaches their skull and then read the height from the dial.
Obviously, this isn't much of a portable option since you fix it to the wall. You also have to take great care to ensure you position the equipment correctly and accurately. If you're a mm or so out, then ALL of your readings will be out by the same amount. Combine this with the fact your clients may be standing on a carpet and you can very quickly build in some large error into your measurements.
I also found the dial on this model often hard to read, particularly with clients who were taller than me. There is a faint red line marking the height, which is best read at eye level. If you're particularly short and measuring particularly tall clients, you might struggle to read this one accurately.
Skinfolds measuring equipment - body fat calipers (or callipers depending where you're from)
Realistically there's only ever going to be one option here. I use the Harpenden Skinfold Caliper by Baty International.
Anyone who's anyone within the fitness industry with an interest in body composition will be aware of these calipers. By many accounts, they're the industry standard when it comes to measuring skinfolds.
Many of the initial studies correlating skinfold measurements with bodyfat percentage used Harpenden calipers. They're accurate and reliable (if used correctly). Indeed may competitors design their own version of skinfold calliper to be 'comparable with Harpenden'. Enough said.
They're pricey, I'm not going to lie.
But with care, and when used properly, they'll offer a lifetime of accurate and reliable skinfold measurements.
Other calipers used in the past - Slim Guide Skinfold Calliper
These are very much a 'budget' option when it comes to body composition assessment and skinfold calipers. They're affordable, made of plastic and are available from a range of suppliers.
They're main drawback though is the lack of accuracy and therefore, reliability.
The measurement scale is in 1mm increments (compared with Harpenden's precision to 0.1mm). Measurement is by simple means of an arrow that moves in direct proportion to the jaws opening and closing. While they may give a quick reading, I wouldn't advise you to use these for any client work. They're just not reliable enough.
Another point to bear in mind is they're made from moulded ABS plastic. Check over all surfaces, particularly the inside of the jaws that will be in contact with the skin. You might find there are sharp edges which you need to file down using fine sandpaper or an emery board to avoid discomfort.
They can be a good tool if you're just getting started with skinfolds and allow you to practise somewhat before outlaying considerably more for the Harpenden option.
Measuring Tapes - the most important body composition assessment tool
Perhaps the most vital piece of equipment in my anthropometric toolbox.
A tape measure is obviously useful to assess girth measurements, like waist and hip circumference. It's also essential in order to measure and assess skinfolds accurately. You have to be sure the skinfold site you are measuring is in exactly the right spot. And that's where a good tape measure that's accurate and reliable comes in.
The tool I use is the Lufkin Slimline Executive girth tape.
Now, if you're not anthropometrically trained, you may not be familiar with exactly what a girth tape is. You won't find this tape measure in many sports or fitness stores or health shops.
Instead, you'll tend to find it in tool shops and hardware supply stores. It's mainly designed for one, very specific use. Measuring the diameter of tree trunks (or pipes).
You see the tape is double-sided. One side has the all familiar mm and cm-scale but the other displays Pi measurements. You see, if you wrap the tape around any cylindrical object, like a tree trunk or pipe, and read the scale it'll instantly tell you the diameter of the object. (Since Pi multiplied by diameter gives circumference, in case you can't remember back to your high school maths lessons.)
That's all well and good, but his tape has several important features that make it ideal for measuring parts of the body.
It's small and lightweight for starters. When measuring clients, you don't want anything big and bulky that's going to slow you down or get in the way of accurate measurements.
The tape itself is made of steel - not fabric, fibreglass or plastic. As a result, there's no 'give' or stretch when taking measurements. Plastic tapes, over time, can often become stretched just by the simple action of pulling too tightly with each measurement. This will mean that your tape will lose its reliability. You won't get that with a steel tape.
Finally, the tape itself is very thin - only a little over 6mm (1/4 inch) wide. This increases the accuracy considerably when measuring girth since a wider tape introduces more error into the measurement.
Other tapes I've used
I have, in the past, enjoyed using the Bodycare Anthropometry Tape.
This tape is especially useful for taking girth measurements. It has a lockable, retracting fibreglass tape with a specially designed hook at the end. As a result, you can clip the tape to itself and let go - the tape will stay put.
This allows you to set the tape, let go and take a few steps back to check its positioning. For super-accurate measurements, you want the tape to sit level, perpendicular to the floor and without any twisting or bunching up. The Bodycare tape allows you to take a full 360-degree walk around, from a distance, before taking a measurement.
If you only want to measure girths, then this is a great tape.
The last part of the ISAK Restricted Profile, which I perform for some clients, involves measuring bone breadths. To do this, you need a set of bone calipers.
Essentially, these are a set of modified vernier calipers that are designed not to have any sharp points or edges that would otherwise cut the client's skin.
I've used a couple, but my favourite are the Cescorf 16cm bone calipers.
This is an example of a piece of equipment where more expensive doesn't necessarily mean better quality. These 16cm calipers are the more affordable Cescorf option and in my view are the more reliable. They're sturdy, made of ABS plastic and have a clear, easy-to-read measurement scale.
When used properly, they'll give reliable and accurate results.
I have used Cescorf's more expensive bone calipers but I don't like them.
They do come with a handy carry case which is good if you're looking for portability. They dismantle into component parts though and this is where I find the problem.
The arms themselves slide in and out of the main scale and there is a bit of wobble in them. For me, this makes it near on impossible to get a truly accurate reading from these calipers. That being said, they are made of metal so are potentially more durable than the plastic option. You just need to take care to ensure you set and calibrate them correctly.
Other measurement tools and accessories for body composition assessments
That covers all the main equipment I use for all of the measurements I take when tracking clients.
The following are additional tools which are nice to have and certainly make the task easier. They are by no means essential for getting accurate measurements though.
Simply put, a segmometer allows you to easily measure 'segment' length. For example, the length of the ulna, or determining the midpoint of the upper arm. This measurement is useful when determining certain skinfold sites. For instance, the biceps and triceps skinfold sites are both determined relative to the mid-point of the humerus. Or more technically, the equidistant point between the acromiale and radiale landmark sites.
You can find the mid-point, and measure segment lengths, using a standard measuring tape. Indeed, many anthropometrists do. A segmometer just makes the process much simpler, easier and potentially more accurate.
I sometimes use the Cescorf segmometer, but often I don't bother with it.
At its most basic level, a segmometer is just a measuring tape with protruding 'fingers'. These fingers allow you to measure straight-line distances without having to worry about curvature of the skin or wrinkling of clothing, etc.
A real anthropometry box is a wooden structure with set dimensions. Clients will sit and stand on the box at various times to have certain measurements taken. A proper anthropometry box also has notches cut out, similar to a toe-kick on a kitchen cabinet. This cut out allows you to stand right up to the edge of the box without your feet or toes getting in the way.
Having your client stand on a raised platform, like a box, gives several advantages.
When taking measurements, like waist girth, the client's waist will be closer to eye-level. It's far easier (and more accurate) to read a tape that's already at eye level without having to crouch down to view it.
Similarly, for skinfold sites like front thigh, the client needs to sit down.
That being said, for what it is, an anthropometry box is expensive. It's precision-made, large, bulky and, being wooden, it's heavy. Shipping costs can be prohibitive.
My preferred option is to use a Gorilla 150kg Industrial Safety Step.
These are portable, easy to buy at a range of hardware stores as well as being strong and sturdy. (I bought mine at Bunnings)
They do come topped with high-grip strips though. These can be very rough, almost like sandpaper and not very comfortable to sit or stand on. I have a small square of high-density foam matting placed on top of mine to give better comfort to my clients.
Want me to measure your body composition?
If you live in the Perth area, get in touch to arrange your own personal body assessment.
We'll go over the entire ISAK protocol and you'll get a complete report showing girths, skinfolds, bodyfat and other measurements.