BOD-POD is also known as

Question

Accepted Answer

The correct option is (1):
The BOD POD is the trade name for a device that uses the technique of whole-body **Air Displacement Plethysmography (ADP)** to measure body composition. This sophisticated technique is based on a well-established scientific principle: Boyle's Law. In simple terms, Boyle's Law states that when temperature is held constant, the pressure and volume of a gas are inversely proportional. The BOD POD measures the change in pressure within a sealed chamber when a person sits inside it, which allows for the very precise calculation of the person's body volume. By combining this calculated volume with the person's mass, the device then estimates their body density, which is finally used to determine the percentages of fat mass and fat-free mass in the body. Therefore, the technical name for the methodology used by the BOD POD is Air Displacement Plethysmography.

The incorrect option is (2):
The **Specific gravity method** is a general term often associated with Hydrostatic Weighing, or Underwater Weighing. This method determines body volume by measuring the amount of water a person displaces when fully submerged, based on Archimedes' Principle. While the goal is the same—to find body density and then body composition—the physical method relies on water displacement rather than air displacement. The equipment, procedures, and core physics principles (Archimedes' versus Boyle's Law) are entirely different, making this a distinct technique from the BOD POD.

The incorrect option is (3):
**Dual energy absorptionmetry**, more commonly known as Dual Energy X-ray Absorptiometry (DEXA or DXA), is a method that uses two low-dose X-ray beams to scan the body. It is considered a gold standard in body composition measurement because it is a three-compartment model, separately analyzing fat mass, lean mass, and bone mineral density. Unlike the BOD POD, which measures volume via air pressure changes, DEXA directly measures the differential attenuation of X-rays through the different tissues. These are two completely distinct technologies, so it is incorrect to use the term interchangeably.

The incorrect option is (4):
The statement **All options are wrong** is incorrect because Option 1, Air displacement plethysmography, is the technically correct term for the operating principle of the BOD POD. The BOD POD device is merely a brand name for an air displacement plethysmograph. Therefore, since the accurate, technical description of the equipment is provided in Option 1, this option cannot be the correct choice.