Rights and Plant-based athlete recipes Open Access This article is published under license to Spectroscopyy Central Ltd. Simple devices impedabce estimate BIA impedance spectroscopy fat, often using BIA, spectroscpy available to consumers as body fat meters. It is considered that the upper body BIA device is more suitable for small form-factor wearable devices such as a wristwatch 8. Validity of bioelectrical impedance measurement in predicting fat-free mass of Chinese children and adolescents. Article PubMed Google Scholar Heitmann BL.

BIA impedance spectroscopy -

Is Bioelectrical Impedance Analysis valid and reliable? Are there issues with Bioelectrical Impedance Analysis? Is future research needed with Bioelectrical Impedance Analysis? Conclusion References About the Author. Figure 1. The difference in bioelectrical conductivity between muscle and fat.

References Buccholz, C. Bartok and D. Franssen, E. Rutten, M. Groenen, L. Vanfleteren, E. Wouters and M. Schlager, R. Stollberger, R.

Felsberger, H. Hutten and H. Bergsma-Kadijk, B. Baumeister and P. Sun, C. Chumlea, S. Heymsfield , H. Lukaski, D. Schoeller, K. Friedl, R. Kuczmarski, K.

Flegal, C. Johnson and V. French, G. Martin, B. Younghusband, R. Green, Y. Xie, M. Matthews, J. Barron, D. Fitzpatrick, W.

Gulliver and H. Salle, M. Audran and V. van Marken Lichtenbelt, F. Hartgens, N. Vollaard, S. Ebbing and H. Jebb, T. Cole, D. Doman, P. Murgatroyd and A. Chouinard, D. Schoeller, A. Watras, R.

Randall Clark, R. Close and A. Evans, M. Saunders, M. Spano, S. Arngrimsson, R. Lewis and K. Melchiorri, S. Volpe and A. Clark, C. Bartok, J. Sullivan and D.

Gleichauf and D. Saunders, J. Blevins and C. Weststrate, I. Paymans and K. Bouchard, A. Tremblay and J. The simplicity of BIA measurements, a cost effective design and the simple visual representation of impedance data enables patients to compare and determine body composition during the time course of a specific treatment plan in a clinical or home environment.

Published in: IEEE Transactions on Biomedical Circuits and Systems Volume: 10 , Issue: 4 , August Article :. Date of Publication: 03 February The advantage of the multiple electrode devices is that body segments may be measured simultaneously without the need to relocate electrodes.

Results for some impedance instruments tested found poor limits of agreement and in some cases systematic bias in estimation of visceral fat percentage, but good accuracy in the prediction of resting energy expenditure REE when compared with more accurate whole-body magnetic resonance imaging MRI and dual-energy X-ray absorptiometry DXA.

Impedance is frequency sensitive; at low frequency the electric current flows preferentially through extracellular water ECW only while at high frequency the current can cross cell membranes and hence flows through total body water TBW. In bioimpedance spectroscopy devices BIS resistance at zero and infinite frequency can be estimated and, at least theoretically, should provide the optimal predictors of ECW and TBW and hence body fat-free mass respectively.

In practice, the improvement in accuracy is marginal. The use of multiple frequencies or BIS in specific BIA devices has been shown to have high correlation with DXA when measuring body fat percentage. The electrical properties of tissues have been described since These properties were further described for a wider range of frequencies on a larger range of tissues, including those that were damaged or undergoing change after death.

In , Thomasset conducted the original studies using electrical impedance measurements as an index of total body water TBW , using two subcutaneously inserted needles.

In , Hoffer concluded that a whole-body impedance measurement could predict total body water. The equation the squared value of height divided by impedance measurements of the right half of the body showed a correlation coefficient of 0. This equation, Hoffer proved, is known as the impedance index used in BIA.

In , Nyober validated the use of whole body electrical impedance to assess body composition. By the s the foundations of BIA were established, including those that underpinned the relationships between the impedance and the body water content of the body. A variety of single-frequency BIA analyzers then became commercially available, such as RJL Systems and its first commercialized impedance meter.

In the s, Lukaski, Segal, and other researchers discovered that the use of a single frequency 50 kHz in BIA assumed the human body to be a single cylinder, which created many technical limitations in BIA.

The use of a single frequency was inaccurate for populations that did not have the standard body type. To improve the accuracy of BIA, researchers created empirical equations using empirical data gender, age, ethnicity to predict a user's body composition.

In , Lukaski published empirical equations using the impedance index, body weight, and reactance. In , Kushner and Scholler published empirical equations using the impedance index, body weight, and gender.

However, empirical equations were only useful in predicting the average population's body composition and was inaccurate for medical purposes for populations with diseases. The use of multiple frequencies would also distinguish intracellular and extracellular water.

By the s, the market included several multi-frequency analyzers and a couple of BIS devices. The use of BIA as a bedside method has increased because the equipment is portable and safe, the procedure is simple and noninvasive, and the results are reproducible and rapidly obtained.

More recently, segmental BIA has been developed to overcome inconsistencies between resistance R and the body mass of the trunk. In , an eight-polar stand-on BIA device, InBody , that did not utilize empirical equations was created and was found to "offer accurate estimates of TBW and ECW in women without the need of population-specific formulas.

In , AURA Devices brought the fitness tracker AURA Band with built-in BIA. In BIA became available for Apple Watch users with the accessory AURA Strap with built-in sensors.

The impedance of cellular tissue can be modeled as a resistor representing the extracellular path in parallel with a resistor and capacitor in series representing the intracellular path, the resistance that of intracellular fluid and the capacitor the cell membrane.

This results in a change in impedance versus the frequency used in the measurement. Whole body impedance measurement is generally measured from the wrist to the ipsilateral ankle and uses either two rarely or four overwhelmingly electrodes.

In the 2-electrode bipolar configuration a small current on the order of μA is passed between two electrodes, and the voltage is measured between the same whereas in the tetrapolar arrangement resistance is measured between as separate pair of proximally located electrodes.

The tetrapolar arrangement is preferred since measurement is not confounded by the impedance of the skin-electrode interface [23]. In bioelectrical impedance analysis in humans, an estimate of the phase angle can be obtained and is based on changes in resistance and reactance as alternating current passes through tissues, which causes a phase shift.

A phase angle therefore exists for all frequencies of measurement although conventionally in BIA it is phase angle at a measurement frequency of 50 kHz that is considered.

Thank you for Strategies for craving moderation nature. Strategies for craving moderation are using a browser version with impsdance support for CSS. To Blood pressure management techniques the spectfoscopy experience, we spectroscopj you impedanxe a more up to date browser or turn off compatibility mode in Internet Explorer. In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Bioelectrical impedance analysis BIA is used to analyze human body composition by applying a small alternating current through the body and measuring the impedance.

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Bioelectrical Impedance Analysis (BIA)