An accumulative body of literature concludes that a sedentary lifestyle elicits detrimental changes in body composition (BC), such as a dramatic increase in fat mass leading to obesity, or a loss of lean muscle tissue leading to premature sarcopenia 1,2. These factors considerably increase the risk of developing certain diseases, including some types of cancer, diabetes and cardiovascular diseases 3,4. It is also known that adopting a healthy diet and chronic physical activity promotes positive BC profiles in different populations 5, 6, 7.

According to the American College of Sports Medicine 8, BC is considered as one of the components of the physical fitness, and a wide array of methods for estimating it exist. These range from basic anthropometric measures to highly specialized techniques such as nuclear magnetic resonance (NMR) and dual energy X-ray absorptiometry (DXA). The DXA technique is currently considered as one of the gold standards for determining BC in terms of bone mineral density (BMD), bone mineral content (BMC) and total and regional lean mass and body fat (BF), usually expressed as a percentage of total body mass (i.e., BF%). The DXA technique is considered a valid, accurate and reliable method for estimating BC variables, with a measurement error <2% when performed properly 9.

The principle by which the DXA technique is based relies on the measurement of the X-rays transmission through a body at high and low energy (i.e., dual energy). The X-ray source generates an X-ray beam, which consists of photon particles carried by electromagnetic energy, and as photons pass through the person's tissues, physical interactions occur that reduce or attenuate the intensity of the beam. This attenuation (i.e., absorptiometry) depends on the energy of the photons and the density and thickness of the tissues through which they pass 10.

The evidence suggests that between 10% and 90% of the tests performed with DXA present one or more errors 11,12. Different factors have been reported that might negatively affect the validity and reliability of the values ​​obtained with DXA (e.g., body positioning, hydration status) 13. These errors may represent a significant problem for a costumer or a research participant when conducting measurements in which it is expected to detect even small changes in BC variables. Thus, not only technical (i.e., external to human) but also biological variability (e.g., tissue hydration) can affect DXA values ​13.

There is scarce evidence on the effect of textile materials that exert some kind of compression on BC as assessed by DXA in humans. These materials might attenuate the intensity of the X-rays reaching the tissues. However, evidence exists for BC as assessed by air displacement plethysmography (e.g., Bod Pod®) 14,15. For instance, Shafer et al. 15, analyzed whether participants’ clothing and body mass index (BMI) affected the validity of air displacement plethysmography in adults when comparing this technique with DXA. Significant differences were found between both techniques according to the garments used (i.e., scrubs, T-shirt + shorts, spandex) and the BMI classification (i.e., normal, overweight, obesity), underestimating or overestimating the results.

McNamara et al. 16, analyzed whether the use of radiolucent clothing (while wearing a robe and heavy winter clothing) contributed significantly to the observed measurement error on BMD measured with DXA. The scans were performed to a spine phantom, obtaining a significant small effect on the mean BMD and the measurement error. Siglinsky et al. 17, analyzed a larger number of clothing (e.g., dense or synthetic, and reflective materials) and its effect on bone and soft tissue mass as determined by DXA. The type of garment significantly increased lumbar spine BMD, total BMC, total body fat and lean mass. Lean and fat mass were also affected by metallic threads, wool, blended denim, and shiny polyester, and lean mass was affected by cotton and sweatshirt material.

In spite of the evidence, no studies have been found on the effects of compression textiles on body composition as measured by DXA. Compression materials as those found in several fitness and sport garments might produce a “sausage effect” by compressing body tissues, which might add noise during DXA scans. For instance, underestimations above 2% in BF percentage have been reported for different garments during air displacement plethysmography assessment 14. Therefore, the purpose of this study was to determine the effect of a compression bandage on BC scores as assessed by DXA.