Omron Healthcare HBF-500 User Manual

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USEFUL INFORMATION
PRINCIPLE OF BODY COMPOSITION CALCULATION
What is the Bioelectrical Impedance Method?
The HBF-500 estimates the body fat percentage by the Bioelectrical Impedance (BI) method.
Muscles, blood vessels and bones are body tissues with high water content that conduct electricity
easily. Body fat is tissue that has little electric conductivity. The HBF-500 sends an extremely weak
electrical current of 50 kHz and less than 500 µA through your body to determine the amount of each
tissue. This weak electrical current is not felt while operating the HBF-500.
How to Calculate the Body Composition
The following methods have been the established method for accurate evaluation of body composition.
Body Fat Percentage: This is based on the DXA (Dual Energy X-Ray Absorptiometry) method,
which uses two different x-rays to make a quantitative assessment of the amount of fat in the body.
Resting Metabolism: This is based on exhalation analysis, where the composition of exhaled air is
analyzed. This makes it possible to calculate the resting metabolism by measuring the consumption of
oxygen in exhaled air.
Visceral Fat Level: This is based on MRI (Magnetic Resonance Imaging) analysis, which uses
nuclear magnetic resonance to make non-intrusive images of the body. This makes it possible to
calculate the area of visceral fat at cross section of abdomen.
Skeletal Muscle Percentage: This is based on MRI (Magnetic Resonance Imaging) analysis,
which uses nuclear magnetic resonance to make non-intrusive images of the body. This makes it
possible to calculate the amount of skeletal muscle in the body.
Omron has developed a formula referring to the above methods. The body composition is calculated
by a formula that includes five factors: electrical resistance, height, weight, age and gender.
Measures the whole body to avoid the influence of fluctuations
The ratios of the water in your upper body and lower body may change through the day. This means
that the electrical impedance of the body also varies. Since the HBF-500 uses electrodes for both the
hands and feet to take measurements, it can reduce the influence of water movement on measurement
results. 
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