BIO ELECTRICAL IMPEDANCE ANALYSIS TOTAL BODY

Instructions for estimating body composition using the Valhalla Bioimpedance Body

Composition Analyzer (BIA-1990B).

1. Record pertinent identification data on the top section of the data sheet. Give the

name of the measurer and time and date of the measurement.

2. Record the subjects height and body weight (these measurements should be

obtained during the same test session as the impedance measurements).

Subject Preparation and Position (Steps 3-4)

3. The subject must remove only the right shoe and sock. The dorsal surface of the

right hand and the anterior surface of the right ankle must be exposed and dry.

4. The subject must be lying supine for approximately five minutes before the

impedance measurement is made. The legs should be extended (knees straight)

and spread so that the thighs do not touch. The arms should be extended, next to

the body, relaxed, but not touching the body. The entire body should be relaxed.

Breathe normally.

Electrode Placement (Steps 5-9)

5. Body electrical impedance is measured using a four-surface electrode technique

between the right hand and right foot (see below). The tetrapolar electrode

technique is utilized because it minimizes contact resistance, or electrode-skin

interaction, at the signal or current-inducing probe electrode site. The first

electrode pair emits a constant source current of 50 kHz at 800 microamps. The

second electrode pair measures the alternating current voltage drop (E = I x R) as

impedance. The impedance signal is then vectored into the electrical components

of resistance and reactance. Proper electrode placement is critical.

6. Prior to attachment cut the electrodes in half, bisecting the protruding tab. The

cut edge of the electrode, when placed on the ankle and wrist, should face toward

the shoulder and thigh. Electrode gel is not needed.

7. Place electrodes on right hand as follows:

a) Put H-1 (red cable, black tip) on an imaginary line between the styloid

processes of the radius and ulna.

b) Put H-2 (red cable, black tip) on an imaginary line just above the

metacarpal-phalangeal joint line.

c) H-1 and H-2 should be placed parallel and directly across from each other.

8. Place electrodes on right foot as follows:

a) Put F-1 (black cable, red tip) on an imaginary line bisecting the medial and

lateral malleoli.

b) Put F-2 on an imaginary line just above the metatarsal-phalangeal joint

line directly across from F-1.

9. The orientation of the cable clips in relation to the right thumb and right lateral

malleolus is important. The clips on the right hand should be connected adjacent

to the thumb, and the clips on the right ankle are adjacent to the lateral malleolus.

Obtaining the Resistance and Reactance Measurements (Steps 10-16)

10. The Valhalla bioimpedance body composition analyzer (BIA-1990B) may be

operated with the analyzer plugged in or not, as you wish. Normal adult values

for resistance fall between probably not charged, and the analyzer must be

plugged in to obtain accurate readings.

11. To operate the analyzer with the battery charger, plug the male end of the power

cord into a 110-volt AC wall outlet (the charger and analyzer should be off).

Plug the female end of the power cord into the connector located in the upper

right hand corner of the BIA-190B. Turn the battery charger and BIA-1990B

switch on.

12. The electrode cables should be plugged into the connector located in the lower

right hand corner of the front of the BIA-1990B analyzer.

13. Two switches are located on the front of the analyzer. The leftmost switch is a

range selector and should be set at 0-1000. The right switch, when in the up

position (Res), allows the resistance measurement to be displayed, and when in

the down position (Reac), reactance is displayed.

14. Obtain the resistance and reactance readings. Allow a few seconds for the reading

to stabilize before recording the result.

15. Wait one minute and repeat Step 14.

16. Wait an additional minute and repeat Step 14. Use the average of the three

readings for the representative resistance and reactance measurement.