This method still has the potential disadvantage that if a steel rod is dropped (or thrown) it could chip a pool deck tile or hurt someone. This approach should cost you less than $5 in steel, and it should provide an accuracy of around 3% regarding the bodyfat percentages. If you intend to regularly measure your bodyfat percentage (every week or every month), we recommend using one of the other weight sets. The better accuracy can give better feedback about your success in your Progress Chart!
These steel weights should be spray painted with rust-resistant paint to keep the steel from rusting. It is a good idea to slightly grind or sand the edges so no one would get cut by a sharp edge.
It is our hope that enough YMCAs and Health Clubs near you will have the precision set of bodyfat batons and that they will offer either a free service or a nominal ($1) charge to test bodyfat analysis that few people would see reason to need to make their own!
|STEEL RODS 1||Letter|
|1/2" steel rod 8.25" long||Ds|
|3/4" steel rod 7.375" long||Hs|
|3/4" steel rod 11.0" long||Ls|
|1" steel rod 8.25" long||Ps|
|1" steel rod 10.25" long||Ts|
|1 1/4" steel rod 8.0" long||Xs|
|two steel rods above||Xs+Ds|
|two steel rods above||Xs+Hs|
|two steel rods above||Xs+Ls|
|two steel rods above||Xs+Ps|
|two steel rods above||Xs+Ts|
|9.75" long 3" diameter empty PVC pipe with caps||float|
|11.25" long 4" diameter empty PVC pipe with caps||FLOAT|
These floats can also be made out of 1" thick blue foam building
insulation. The 'float' would be cut as a rectangle of 6" by
12.5". The 'FLOAT' would be cut as a rectangle of 10" by
15". Such floats are not very durable and are fairly easily
damaged, where chunks can get lost and their accuracy then degrades.|
The Analysis Charts for the Steel Rods are:
For body weights of up to 130 pounds
For body weights of between 130 and 230 pounds
For body weights of between 230 and 330 pounds
The Progress Chart is at:
Weekly or Monthly Progress Chart
Have a "normal" amount of air in your lungs, NOT having severely exhaled or inhaled. And then simply float stationary! Your friend sees (or maybe even measures) how much of your head sticks out of the water! If you do NOT float and sink toward the bottom, your bodyfat is likely to be around 13% or lower. If your friend sees TWO INCHES of the top of your head above the water, you are likely to be around 24%. If your friend sees about FOUR INCHES (essentially to the very top of the earlobes), you are likely to be around 40%. If around SIX INCHES (essentially to the earholes, and your eyes are above the water) then you are likely to be around 57%. You might see from the large changes in bodyfat numbers due to rather small differences in the amount of the head being visible, that this method is only very approximate, with plus-minus 10% being expected. It only provides a ball-park number!
We mention this because there are a LOT of people who have been told that they have 8% or 4% or 11% bodyfat, due to using the extremely inaccurate bodyfat caliper method or electrical impedance (methods absolutely proven to regularly be 15% off either way, so in other words, meaningless except for bragging purposes.) A person could try to alter this method by intentionally normally exhaling first, which makes you float around one inch lower, which would appear to give an estimate of around 6% lower. By attempting to exhale all the air you can, you can lower your body by about 3 inches, which can give the appearance of around 16% lower estimate. The point is that by simply altering the amount of air in your lungs, you could change this reading by as much as 16%, another indication of why the far more accurate and repeatable Batons and Floats is desirable. If you really want to believe that you are at 8% or 11% so you can brag to your friends, there are many ways you can create such a number. However, if you actually want a REAL number for bodyfat, this very crude method can get you within about plus-minus 10%, and the Batons-Floats can get you within about 1%.
Bodyfat - Combating Childhood Obesity Through Motivation (specifically directed at Childhood Obesity)
The page that has the Bodyfat Percentage - Determining Accurate Bodyfat Easily Bodyfat Calculator which uses the Baton/Float letters and the dry body weight can calculate the correct density and bodyfat values for essentially anyone between 30 pounds and 800 pounds and with essentially any percentage of bodyfat.
This page - -
- - is at
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