... little body fat and obesity. There are many accurate laboratory based techniques to attain such measurements; for example hydrodensitometry, dual-energy x-ray absorptiometry (DXA), isotope dilution, and air displacement plethysmography. (Wagner & Heyward, 1999). These techniques are often used for research work, but generally are too expensive, time consuming, and impractical for use in field evaluations, gym environments and healthcare settings (Vogel & Friedel, 1992, Swan & McConnell, 1999). A number of field techniques solve the problems, outlined above, and have the added benefits of being portable, are relatively simplistic to use and are noninvasive (Lukasaki, Bolonchuk, Hall & Siders, 1986). They do, however, have limitations of lower accuracy and validity (Vogel & Friedel, 1992). Field methods such as Skinfold (SkF) tests, bioelectrical impedance analysis (BIA), circumference measures, and near infra-red interactance (NIR), are all doubly indirect, and are based upon regression models devised by comparing measure to criterion measurements (Williams, ...

See this essay or coursework document in full right now