Hydrostatic Body Composition Testing


2017 New Year, New You Contest - Hydrostatic Body Composition Testing

If you've ever wanted to get started on a plan to make real progress, or want to get back on track, getting your body fat tested in our hydrostatic tank is a great way to precisely benchmark your fitness. Getting dunked takes just 10 minutes, and afterward, you'll get a detailed report to keep, showing:

  • Your fat and fat-free body mass, as percentages and in actual weight
  • How much fat, if any, you need to lose to achieve your desired body composition
  • How many calories per day you burn without exercising—unique to you
  • How many calories you burn from different exercises—again, specifically for your body
  • Where you are on a scale of ideal body fat for your age and gender
  • Your history, if you've been tested before

What is Hydrostatic?

Adj. Hydrostatic - Relating to fluids at rest or to the pressures they exert or transmit; "hydrostatic pressure." When you think hydrostatic, just think water. Water has a very specific density. When you are weighted underwater your density can be measured and comparing this to your dry weight we can very accurately determine how much is lean and how much is non lean mass. This ratio is what we call your “body fat percentage”.

Hydrostatic body composition testing is the most accurate method of measuring the amount of fat and lean (fat-free) mass a person has on his or her body. Just as a person weighs a different amount on the Moon than on Earth, a person weighs differently underwater than on land. Using measurements of a person's weight underwater and weight on land, precisely how much fat a person carries can be calculated.


What should I wear/bring?

Bring a towel and a snug fitting bathing suit. Baggy clothes will capture air and may influence test results. Also, please take a shower if you just worked out and don’t wear heavy makeup, hair gel or lotion. Although drinking water and exercise will not affect your results eating a big meal within two hours of the test can.

How do I prepare for a Test?

Here’s all you need to do:

  1. Get ready to get wet and go all the way under water.
  2. Don’t eat a big meal within 2 hours of your test.
  3. Go to the bathroom if you need to and take a shower if you can. Drinking water or working out prior to the test will not affect your results.

Is the tank water clean? Warm?

Yes. The water in the tank is continuously filtered while the clinic is in operation, chlorinated, pH balanced, and approximately 90° F. The clinic is also heated and/or cooled depending on the weather.

How accurate is it?

There is no other method in existence that is more — or as — accurate as hydrostatic testing. It's impossible to say that it's some-percentage (e.g. 99.9%) accurate, or what the "margin of error" is. To say that, there would have to be a better method of determining body fat than hydrostatic testing to compare to. The accuracy of other methods like caliper testing or BOD POD do have margins of error—because their accuracies are a measure of how close their results are to hydrostatic testing. If there was a better method we would use it. We strive to use the latest technology to achieve the most accurate results.