The thing to note about consumer body composition scanners like bathroom scales that do impedence, they are nowhere near as accurate as commercial scanners like the DEXA or InBody. The DEXA is considered a gold standard in body composition testing. Hydrostatic or underwater weighing involves submerging a person in water to measure body density. Because muscle and bone are denser than water and fat is less dense, this method can provide accurate estimates of body composition. However, hydrostatic weighing requires specialized equipment and facilities, making it less accessible and more expensive than other methods. As of 2025, a DEXA at the University of Calgary costs $100 per scan.

The Bod Pod is $75 per scan. Air displacement plethysmography, the Bod Pod, measures body composition by determining body volume and density. The individual sits in a sealed chamber, and the machine measures the air displaced by the person’s body. This method is quick, non-invasive, and relatively accurate. The range of error is 1-2.7% as compared to a DEXA.

The InBody scanner was designed as a close competitor to the DEXA and Bod Pod and is 98% as accurate but very affordable at $35/scan for non-members at Rage Fitness and is included for members. An InBody scan uses bioelectrical impedance analysis (BIA) to measure body composition by sending low-level electrical currents through the body and analyzing the resistance of different tissues.

Rage Fitness has compared the InBody 270 at Rage Fitness against other scanners like the Bod Pod and Renpho bathroom scale. The variance between the Bod Pod and InBody 270 is only 1%. The Renpho and InBody had almost a 5% variance.

As a consumer, you need to be aware of the differences so that you are not disappointed when the commercial scanners estimate your body fat percentage to be a lot higher or lower than your bathroom scale. That doesn't make any scanner "inaccurate", it just means there are more complex and sensitive inputs and methodologies that the commercial scanner relies on for greater accuracy of data. The technology in a bathroom scale and various commercial scanners is incomparable.

 

Renpho Bathroom Scale

 

Bod Pod Scan

 

InBody 270 Scan

In order to have the most accurate results possible with the InBody 270, Rage Fitness recommends the following guidelines:

• No eating or drinking 3-4 hours prior to the scan.

• No caffeine 24 hours prior to the scan.

• Client must go to the washroom and remove any extra clothing and metal accessories before stepping on the scale. Remove all jewelry, watches, wallet, cell phones, jackets, etc.

• Client should repeat the reading at the same time of day each time for consistency. First thing in the morning is ideal.

• Client cannot do vigorous exercise for 6-12 hour prior to the test.

• Client cannot have showered or used a sauna immediately prior to the test.

• Client may not have applied lotion to hands or feet immediately prior to the test.

• Female clients may not be pregnant or menstruating. Please wait to test when you are in the follicular or luteal phase of your cycle, and avoid testing 3 days before, during and 3 days after your period due to excess water retention.

• If the client has a pacemaker or any electronic medical device, they cannot use the machine.

The InBody device is calibrated daily and has an accuracy range within 3-5% for body fat percentage compared to the DEXA.

InBody scans can underestimate body fat in adults by 1-4.8% and overestimate it in children by 0.3-2.3%. If the client has a high muscle mass, the InBody may overestimate body fat percentage as it may think weight loss is recommended when the client is already at a healthy weight. This is especially true for bodybuilders, lean and heavyweight athletes.

If you take creatine, it may increase total body water within muscles and affect results. Please avoid taking creatine 24 hours prior to the test, if possible.

If the guidelines are unable to be adhered to prior to your test, consider rescheduling your test for greater accuracy.