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Returning to Bodyscan after 13 weeks, Lee, 46, has lost an incredible 8.5kg of body fat with NO loss in lean mass – in fact he’s GAINED over a kilo of muscle!

Download the main pages of Lee’s Bodyscan report here.

He did it all by himself, following Mike Matthews’s Bigger, Leaner, Stronger programme, which has him lifting five days a week, hitting each major muscle group for about an hour each day plus some high-intensity interval training (HIIT) on the two rest days. His diet was 45% protein, 45% carbs and 10% fat, a customised meal plan provided by Matthews’s Muscle for Life website.

Lee’s Bodyscan DEXA report reveals he has lost fat pretty evenly. Before, his body fat percentage was higher than that of three-quarters of men his age. Now, he’s turned the tables and moved from the bottom quarter to the top quarter!

The highlights of Lee’s journey so far are:

  • Fat loss of 8.5kg (that’s 28% of his original fat)
  • Body fat down from 32.8% to 25.5%
  • Visceral fat down in line with overall fat loss
  • Lean muscle gain of just over 1kg
  • His body fat percentage has moved from the 76th percentile to the 28th
  • Lean mass more evenly distributed than before

If you want to see what your own body fat percentage would be if you lost 8.5kg or how much fat you have to lose to meet a specific fat percentage target, take a look at our body composition and calorie requirement calculators.

To understand DEXA we need to understand a little about how X-rays work.

Traditional X-ray machines work by passing X-rays of a single energy through the patient’s body. The X-ray photons either pass through unaffected or they are ‘attenuated’ (absorbed or scattered) by the body.

The degree of attenuation (ie, how many photons pass through and how many are absorbed by the patient) depends on the thickness of the subject and, for a given thickness, on the density. Thicker and denser materials (like bones) attenuate X-rays more than thinner or less dense ones (like soft tissue).

For the simple identification of broken bones (when all that is needed is an image of the bone), single energy X-rays are all that is required.

To provide data about bone density, however, a problem arises because some of the X-ray attenuation is caused by the soft tissue surrounding the bone. An algorithm behind a single energy X-ray cannot be used to calculate the thickness of two unknown quantities (bone and soft tissue).

Fortunately, X-ray attenuation is also affected by the energy of the photon beam – the higher the energy, the lower the attenuation. By measuring attenuation based on both energy and subject thickness, the software algorithms behind dual-energy X-rays can use two simultaneous equations to calculate the thickness/density of both bone and soft tissue.

Further, since soft tissue is made up of fat and non-fat and if the density of fat is known (approximately 0.9 grams per cubic centimetre) then the mass of fat and fat-free (lean) tissue can be calculated, along with bone mass.

This essentially is the calculation behind DEXA (dual-energy X-ray absorptiometry) body composition measurement.

Accordingly, DEXA is referred to as a 3-compartment model, simply meaning that it measures the density of three components – bone, fat and fat-free soft tissue – to calculate their mass.