T Nation

% body fat

Hi folks just a quickie - based on the “sum of seven sites” measured with calipers how do i go about converting the final amount into a percentage? Thanks in advance…

You need a conversion equation/table![p]
Did you check the search engine? Well never mind, I’m such a nice guy I’ve done it for you. Direct from Jason Norcross’s article on measuring BF%:[p]

  1. Website:[p] www.enforcergraphics.f2s.com/bodyfat.htm [p]
    However, if you’re a “hands-on” guy, here are the equations:[p]

NOTES: SUMS refers to the sum of the average skinfold thickness (mm) of the prescribed skinfold sites. Db refers to body density.
[p]
Male 3-Site Equation (SUM3 = chest, abdomen, thigh)
[p]
Db = 1.10938 - (0.0008267 * SUM3) + (0.0000016 * SUM32) - (0.000257 * AGE)
[p]
%BF = [(4.57/ Db) - 4.142] * 100
[p]
Male 7-Site Equation (SUM7 = chest, midaxillary, tricep, subscapula, abdomen, suprailiac, thigh)
[p]
Db = 1.112 - (0.00043499 * SUM7) + (0.00000055 * SUM72 ) - (0.00028826 * AGE)
[p]
%BF = [(4.57/ Db) - 4.142] * 100
[p]
Female 3-Site Equation (SUM3 = tricep, suprailiac, thigh)
[p]
Db = 1.0994921 - (0.0009929 * SUM3) + (0.0000023 * SUM32) - (0.0001392 * AGE)
[p]
%BF = [(4.57/ Db) - 4.142] * 100
[p]
Female 7-Site Equation (SUM7 = chest, midaxillary, tricep, subscapula, abdomen, suprailiac, thigh)
[p]
Db = 1.097 - (0.00046971 * SUM7) + (0.00000056 * SUM72 ) - (0.00012828 * AGE)
[p]
%BF = [(4.57/ Db) - 4.142] * 100
[p]
Hope this helps. SRS.

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