Monday 2 July 2012

Skinfold Measurements

Making accurate skinfold measurements is more than simply pinching the skin somewhere around a particular area and measuring the thickness. There are precise sites on which the measurements are to be taken. A well-trained technician can obtain accurate results, unlike most others who aren't trained and experienced to take accurate enough results. To take a skin-fold measurement, first determine the correct measurement site. Grab the skin with the thumb and forefinger about 0.5 inch from the measurement site following the natural fold of the skin. Lift the skin up from the muscle, apply the calipers and wait for 4 seconds before reading the calipers (Fat is compressible, so reading the scale before or after the 4-sec delay may affect the results) Readings are usually taken from: Triceps (Midpoint between top of shoulder and bottom of elbow) Chest (Midpoint between armpit and nipple) Abdominal (1inch left and 0.5inch down of belly button) Supriliac (Top of hipbone, in line with belly button) Thigh (Midpoint between knee and hip) Formulas to calculate: Females: Body Density = 1.0994921 - 0.0009929*sum + 0.0000023*sum^2 - 0.0001392*age (triceps, suprailiac, thigh skinfold measurements) Males: Body Density = 1.1093800 - 0.0008267*sum + 0.0000016*sum^2 - 0.0002574*age (chest, abdominal, thigh skinfold measurements) Using those measurements, we can estimate our body fats using two formulas: Siri Percent Fat = [(495 / Body Density) -450] * 100 Brozek Percent Fat = [(4.570 / Body Density) - 4.142] * 100 These are not accurate though, as it assumes that the density of fat-free mass to remain constant. So the actual fat percentage is slightly higher then the measured percentage in the lean, muscular type and vice versa for the obese type. Although we need training and experience, it isn’t very difficult to calculate and estimate our body fat. This also doesn’t require many equipment, except for the special skinfold measuring calipers. As long as we have those, we are able to roughly calculate our body fat anywhere and everywhere. It’s doesn’t cost a lot either. Source: http://www-rohan.sdsu.edu/~ens304l/skinfold.htm Darius Low, S308

1 comment:

  1. sorry this isn't turning out well and I can't seem to get it right...

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