The InBody 230 is a body composition analyzer. This is what it looks like! I’m going to try to answer several questions in this post like…
1. How does it measure your composition?
2. How accurate is it?
3. Who can be assessed and who can’t?
1. The InBody uses BIA (bioelectrical Impedance Analysis) to analyze your body composition. Remember how I said you can’t compare this to calipers? You’d be comparing apples to bananas – because BIA is a technique that measures body impedance by sending an electrical current through the body. NO – you do not feel the electrical current at all, it is very low and very safe. The current only passes through the water fluids inside the body, and based on the impedance values collected, the body water volume is calculated. Since water fluids are usually inside muscle tissues, by using the water volume, the fat-free mass can be calculated. Body fat calipers measure skinfolds to calculate how much subcutaneous fat(fat under the skin) a person has. So, a couple of advantages here by using the InBody – it’s highly accurate and not subject to human error (me pinching in different places) AND you don’t have to put up with getting pinched which is a pain especially if I haven’t filed my nails – and plus, let’s face it – it really puts us in a vulnerable spot. Who likes to take their shirt off and let someone pinch their fat? However – the volume of body water fluctuates (I know this is common knowledge here) to sustain homeostasis in the body – which in turn, will affect each measurement. So – with this in mind, we need to be as consistent as possible by following some standard preset guidelines under the same conditions.
2. How accurate is this? The InBody uses 8-point tactile electrodes – that easily contact the body at 2 points in each hand and foot. All other BIA devices use 4-point tactile electrodes. The 8 point method, divides the body into 5 regions (left and right arm, trunk, left and right leg) with minimal error rate, enhancing measurement reproducibility. The common method using 4 electrodes, divides the body into only 2 regions (the upper and lower body) which gives over-generalized inaccurate results. The 8-point tactile electrode method measures the 5 segments of the body directly, giving pinpoint measurement of each section. This method minimizes the error and detects the body water content and the level of muscle development in each segment.
In addition to this 8-point tactile method, InBody also uses a multi-frequency analysis. Other BIA devices use a single frequency and estimates the amount of intracellular water from the extracellular impedance values. A single, low-frequency current hardly travels through the intracellular water resulting in inaccurate measurements. The proportion of intra and extracellular water is consistent in a healthy body; however, in children, elderly people and obese people their amounts may be imbalanced. Generally, extracellular water is measured by low frequency currents and intracellular water is measured by high frequency currents and it is important to know both. InBody uses a multi-frequency analysis – accurately assessing both intracellular and extracellular water.
Add the 8-point tactile electrodes and the multi-frequency analysis capabilities to the fact that it measures 5 separate segments separately to measure the amount of body water and fat-free mass in each segment – makes for highly accurate results because each measured part isn’t affecting the measurements of the other parts. So it’s not an estimation – but rather a direct measurement.
3. Who can use this and who can’t? It is safe and accurate for kids, elderly and anyone up to 500 lbs. It is NOT good for anyone with implanted defibrillators or pacemakers. Although the electrical current that is sent through the body is extremely low, it is not recommended.