Verdict

Pros

• Portable form factor
• Long battery life
• Accurate body fat results

Cons

• Can be fiddly to use
• App is very basic

What is the Skulpt Chisel?

When you want to ‘lose weight’, what you really mean is that you want to lose body fat. Unfortunately, traditional body fat scales aren’t particularly accurate. The Skulpt Chisel is a handheld body fat and muscle quality analyser that provides a far more accurate gauge of your fat loss and muscle composition.

Its overall accuracy is up to scratch, and it’ll be a great choice for personal trainers, bodybuilders and figure athletes, but issues with the reading process make it ill suited to more casual users.

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Skulpt Chisel – Design and Setup

The Chisel is the second handheld body fat analyser from Skulpt – its first was the Skulpt Aim. Both devices look largely the same, measuring about the size of a large portable battery pack. It’s small and light enough to throw in a gym bag. The main difference is that the Aim included a display and featured a black finish, while the Chisel loses the display and gains a white finish.

As both devices pair with a companion iOS or Android app, the loss of an on-device display isn’t much of an issue, especially as it means the Chisel costs less compared to the Aim (£149). Still, it’s a bit poor that the Aim’s casing has been reused for the Chisel. It means the rubbery navigation buttons on the side make a return, even though they have no actual function.

There’s a multi-coloured LED band that goes around the Chisel’s circumference. This glows either green, red or blue depending on the device’s current status, and makes it easy to know what’s happening, further negating the need for a screen. On the back of the Chisel you’ll find 12 sensors that are used for the actual body fat and muscle quality analysis.

As you need a conducting medium for the sensors to successfully take a reading, a small spritzer bottle is included, which can be filled with regular tap water. A charging dock also comes in the box, but annoyingly this uses a Mini USB cable rather than the more common Micro USB.

Pairing with the Skulpt app couldn’t be simpler, as the app takes you through the necessary steps. You’ll need to sign up to a Skulp account along the way, but the whole setup process only takes a minute or two. After this, the app can turn the Chisel on through Bluetooth LE and have it poised to take readings.

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Skulpt Chisel – Technology

The Chisel can take body fat and muscle readings from 24 different individual muscles. This means you can get specific readings such as left bicep, right quads, left lower back and more. It’s this level of granularity that will appeal to bodybuilders and figure athletes, as it can help identify imbalances and areas that need work.

For more everyday exercisers, you can just do a quick test, which takes readings from three areas: triceps, abdominals and quadriceps, in order to give you an aggregated body fat percentage average. It’s a similar process to how body fat percentage is calculated using calipers and the body fat pinch test.

As for how the Chisel is actually taking a reading, it gets a little scientific, so bear with me. Traditional body fat scales – the type you stand on to take measurements through your feet or require you to hold a special handle – use a method known as bioimpedance.

Fundamentally, a small amount of electrical current is sent through your body and the time it takes to complete a circuit is used to estimate your body fat percentage. This is based on the principle that body fat doesn’t conduct as well as lean mass. This is paired with your age, height and weight and the numbers crunched together to give an estimate of your body fat percentage.

The method isn’t great, as the results can vary wildly from day to day. I’ve personally seen fluctuations as big as 2-3% between two tests only hours apart (the lower your body fat composition, the bigger a percentage difference makes).

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There are variables that can affect accuracy, such as how recently you’ve eaten and your fluid intake, which impact the rate of conductivity. It means that in terms of accuracy, body fat scales have typically sat behind calipers, underwater weighing (also referred to as hydrostatic weighing) and Dual Energy X-ray Absorptiometry (DEXA). Most people won’t have access to a sports science facility to conduct underwater weighing or DEXA tests, so calipers have been the best bet for most, but this can be fiddly and again prone to user error.

Rather than bioimpedance, the Skulpt system uses Electrical Impedance Myography (EIM), which was developed out of methodology used for evaluating neuromuscular disease. In layman’s terms, the current is more targeted towards individual muscle tissue and the numerous sensors are able to measure current flow in different directions and to different depths. It’s therefore better able to identify subcutaneous fat, muscle, bone and skin based on their conductive (and resistive) qualities. It’s also meant to be less susceptible to fluctuations based on the user’s hydration levels and other external factors.

Skulpt also uses these timing measurements to provide what it calls a Muscle Quality (MQ) reading per muscle that is now rated out of 100 following an algorithm change. This takes into account how muscle membranes affect the time delay of the current and measured voltage. The bigger the muscle fibres, the greater their electrical charge storage capacity. This means a greater delay and theoretically a ‘higher-quality’ muscle.

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