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Pengwuino
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So exactly how did that whole idea of dunking yourself in a vat of water measure your body fat? It sounds like some sort of prank!
Protein is slightly heavier than water, and fat is lighter than water.Pengwuino said:So exactly how did that whole idea of dunking yourself in a vat of water measure your body fat? It sounds like some sort of prank!
http://mb-soft.com/public2/bodyfat.htmlHuman body fat has a density of 0.918 gm/cc
I noticed in a swimming class that I took in university, the women had little difficulty floating near the surface, whereas I had to use my arms or legs for some minimal thrust.
Astronuc said:My body fat is low enough (5-7%), that my density is much greater than water, and my neutral bouyancy (with some air in my lungs) is probably a meter or so below the surface.]
Actually, no - because the air in your lungs gets compressed as you sink, there is no neutral buoyancy point. You either sink or float. That's a big issue in scuba diving - maintaining depth or sink/rise rate requires continuous adjustments of buoyancy. Neutral buoyancy points only exist for objects that are more incompressible than water.Astronuc said:My body fat is low enough (5-7%), that my density is much greater than water, and my neutral bouyancy (with some air in my lungs) is probably a meter or so below the surface.
One sinks until the density of the sorrounding water equals one's density, which I agree will have to do with the amount of air in one's lungs. I have participated in submersion density tests where I had to exhale as much air as possible. Even with a lung fully expanded with air, I am about 0.5 m or so underwater.russ_watters said:there is no neutral buoyancy point.
Somewhat of both. I used to be much more active - running, football, cycling (primary mode of transportation in university), etc. Now I sit at a computer most of the day, and I have let my self go.You must be a very active man or have a tweaked metabolism??
It's actually considered to be the most accurate methods of body fat measurement. All of the other forms of measurement are compared to it. Guys like Covert Bailey have dunked thousands of people to develop databases of information and correlations.Pengwuino said:So exactly how did that whole idea of dunking yourself in a vat of water measure your body fat? It sounds like some sort of prank!
Well, right - except that the volume of air in your lungs changes with the surrounding pressure too, but faster than the density of the water changes - which causes your buoyancy to decrease as pressure increases.Astronuc said:One sinks until the density of the sorrounding water equals one's density, which I agree will have to do with the amount of air in one's lungs.
I suspect that another cause - such as surface turbulence - makes it appear that you have an equilibrium point. I am pretty dense too ( :uhh: ) and I have noticed the same phenomena.Even with a lung fully expanded with air, I am about 0.5 m or so underwater.
If your buoyancy stayed positive or increased with depth, you'd never get down.You must begin your dive properly weighted. Buoyancy testing begins at the surface with your BC completely deflated. Take a deep breath and hold it. Assume an upright motionless position. If you are weighted correctly, you will float at eye level in the water.
Submerging, also known as hydrostatic weighing, is a method used to measure body composition by determining the density of a person's body. This is done by submerging the individual in water and measuring the displacement of the water. The more body fat a person has, the more buoyant they will be in the water, leading to a lower density reading.
Yes, submerging is considered to be one of the most accurate methods for measuring body fat percentage. It has a margin of error of just 1-2%, making it more accurate than other methods such as skinfold calipers or bioelectrical impedance.
Yes, there are a few factors that can affect the accuracy of submerging. These include the individual's level of hydration, their lung capacity, and their body composition. It is important to follow proper protocol and have a trained professional perform the test for the most accurate results.
The frequency of submerging to track body fat percentage depends on the individual's goals and their rate of change. For most people, it is recommended to get submerged every 4-6 weeks. However, if someone is actively trying to lose or gain body fat, more frequent measurements may be necessary to track progress.
Submerging is generally considered to be a safe method for measuring body fat percentage. However, it is not recommended for individuals who are pregnant, have a fear of water, or have any medical conditions that may be aggravated by submerging. It is important to consult with a healthcare professional before undergoing this test.