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Prior to beginning, and after you complete your health program, we would highly recommend gathering baseline data with regard to Bio Impedance Analysis (BIA).  This will give us information regarding your Weight, Goal weight, Body fat %, Body Mass Index (BMI), Total Body Water TBW, Muscle Mass, Physique rating, Daily caloric intake DCI, Metabolic age, Bone Mass, and Visceral fat rating. 

Through this intricate testing, we can determine exactly how much progress you've made throughout the program. 

The fee for each test is only $25, and tests can be run as often as once a week throughout the entire program; however we recommend a minimum of two, one in the beginning and yet again upon completion.  Please contact us to schedule your first appointment.

What is Bio-Impedance Analysis?

Bio-impedance analysis (BIA) is the analysis of resistance and reactance in the human body.

The characteristics and composition of a material can be determined by analyzing their effect on an electrical current conducted in the material.

The effect due to energy dissipation is called resistance (R). The effect due to energy storage is called reactance (X). Units of resistance and reactance are called ohms. Resistance and reactance taken together are called the impedance (Z).

Fat-free mass in the human body is proportional to the resistance. Body cell mass is proportional to the reactance.

A bio-impedance analyzer measures resistance and reactance and computes fat-free mass, body cell mass, total body water, and intracellular water.

Studies of large populations have produced equations that yield fat-free mass and body cell mass in kilograms, and water compartments in liters for any combination of resistance and reactance measurements. These studies also establish normal values for populations, and establish the relationship between body composition and health.

To measure resistance and reactance, a bio-impedance analyzer applies a small electrical current to the body via electrodes.

A bio-impedance analyzer is an electronic device containing a precision high-frequency meter, a microprocessor and a printer. This meter, called an impedance meter, measures resistance and reactance. The microprocessor computes the size of the fat-free mass and body cell mass compartments in kilograms and performs all secondary calculations. The printer provides a printout of the results.
Impedance (Z) is the overall propensity of an object to conduct electrical current and is defined as the ratio of the voltage in an object to the current in an object. Its units are ohms, after the physicist.

The constituent components of impedance are resistance (R) and reactance (X). Resistance is a direct indicator of a material's propensity to dissipate energy; reactance is an indicator of energy storage. All materials both dissipate and store energy.

The following electrical characteristics are measured and used to evaluate body composition:

Impedance (Z)
Impedance is a measurement of the ability of a medium to conduct current. It is the ratio of induced voltage to injected current in a conductive medium and has two components: resistance and reactance.

Resistance (R)
Resistance is the component of impedance related to the dissipation of energy in a conductive medium.

Reactance (X)
Reactance is the component of impedance related to the storage of energy in a conductive medium.

Phase Angle (α)
The phase angle is the time delay between a stimulating current and the voltage generated by an alternating current in a conductive medium. The phase angle is expressed in degrees of phase shift.

How do these electrical characteristics relate to each other?
The time relationship of voltage, current, and phase is shown in the first figure below. The vector relationship between impedance, resistance, reactance, and phase angle, represented with polar coordinates is shown in the second figure.
Water is the conductor in the body and determines the resistance.

Electrolytic fluid in fat-free mass consisting of water and charged ions readily conducts electrical current. Extracellular fluid (water and ionized sodium Na+) provides a low-resistance pathway. Intracellular fluid (water and ionized potassium K+) also provides a low-resistance pathway. Fat mass is non-conductive because it contains no water.

Cell membranes within intracellular mass determine the reactance.

The cell membranes consist of a layer of nonconductive, lipophilic material interposed between two layers of conductive molecules. They behave like tiny capacitors - storing electrical charge in the presence of an alternating current.

The extracellular pathway (sodium ionized water) is represented by a single resistance. The intracellular pathway (potassium ionized water and cell membranes) is represented by a resistance and a reactance.

The total resistance is proportional to the amount of fat-free mass. The reactance is proportional to body cell mass (intracellular mass).

Ultimately, the resistance seen by the bio-impedance meter is the total resistance, combining intracellular and extracellular resistance. The meter reports the total resistance and the total reactance to the microprocessor for analysis.

Bio-impedance analyzers use regression equations to compute amounts of fat-free mass, body cell mass, total body water and intracellular water.

What is a regression equation?
A regression equation is a mathematical formula that best predicts the relationship between two or more variables based on the analysis of data sampling. For example, the regression equation for total body water (TBW) is of the form:

TBW = a * Ht2 / R + b * Weight + c * Age + d

The terms are Ht2 / R, Weight and Age. The weighing constants for the terms are a, b, c, and d.

Regression equations for bio-impedance analysis (BIA) are determined through research. For example, to determine the regression equation for TBW, a large number of subjects are analyzed for TBW using deuterium dilution or some other reference standard. Then, resistance, height, weight, gender, and age are supplied for each subject in the study. A computer generates an equation which best describes the relationship between TBW and resistance, height, weight, gender, and age. This process is called regression analysis.

How are regression equations used?
Regression equations are used to compute fat-free mass, body cell mass, total body water, and intracellular water. When the bio-impedance analyzer measures resistance and reactance, the results are passed to the analyzer's microprocessor to perform the calculations. The equations for FFM, BCM, TBW and ICW are encoded into the analyzer's internal software.

Fat-Free Mass
In order to derive fat-free mass in kilograms, a bio-impedance analyzer applies a small alternating electrical current to the body via electrodes. The resistance of the body is measured. Using the measured resistance (R), the analyzer estimates fat-free mass in kilograms.

Body Cell Mass
To derive body cell mass, a bio-impedance analyzer measures both the resistance (R) and reactance (X) of the body. Using the measured resistance and reactance, the analyzer estimates body cell mass in kilograms.

Total Body Water
Using measured resistance, the analyzer estimates total body water in liters.

Intracellular Water
Using measured resistance and reactance, the analyzer estimates intracellular water in liters.

For more information or if you would like to purchase your own Bio Impedance Analyzer visit http://www.tanita.com/IronManScales.shtml