Define Requirements for underwater weighing method?
• The equipment required to perform hydrostatic measurements is bulky and maintenance intense.
• A large tank of water, usually 1000 gallons, must be maintained at a constant temperature.
• Equipment to measure residual lung volume must be utilized.
• Calibrated autopsy scale or its electronic equivalent, connected to an underwater chair is also required.
• Test subjects are asked to exhale as much air as possible from their lungs and be immersed for 10 to 15 seconds for an underwater weight measurement to be taken. This procedure is repeated 7 to 10 times. Total test procedures may require 45 minutes to one hour.
Fear of immersion, fear of infection, obesity and infirmity are barriers to the hydrostatic measurement of accurate body composition analysis; there are also certain limitations, as well as, certain advantages of this method.