A tool for predicting that a person is likely to be abnormally hydrated over a future time interval, and in some cases to alert the person or a medical professional to intervene. From a series of physiological measurements, a tissue electrical impedance spectrum curve, which comprises a phase spectrum curve in an embodiment, is determined and changes in the shape of the curve are ascertained. The measurements may be received using one or more sensors worn by the person. In some embodiments, current and historic spectrum curvature are applied to an evolutionary algorithm, such as particle-swarm optimization (PSO) or differential evolution (DE), to determine an inference regarding the persons future hydration status. In one embodiment, a statistical forecast for the next epoch immediately beyond the present one, is determined.

The inventive concept relates to a body composition analysis system. A body composition analysis system according to an embodiment of the inventive concept includes a sinusoidal signal generator, a synchronous detector, and a bioimpedance analyzer. The sinusoidal signal generator converts a digital sinusoidal signal having a target frequency into an analog sinusoidal signal. The synchronous detector extracts a target frequency component of a bioelectrical signal generated in response to an analog sinusoidal signal based on the digital sinusoidal signal. The bioimpedance analyzer calculates the bioimpedance based on the target frequency component of the bioelectrical signal. According to the inventive concept, it is possible to improve the selectivity for extracting the target frequency component of the bioelectrical signal and to reduce the area and variations of characteristics for the implementation of the integrated circuit.

The inventive concept relates to a body composition analysis system. A body composition analysis system according to an embodiment of the inventive concept includes a sinusoidal signal generator, a synchronous detector, and a bioimpedance analyzer. The sinusoidal signal generator converts a digital sinusoidal signal having a target frequency into an analog sinusoidal signal. The synchronous detector extracts a target frequency component of a bioelectrical signal generated in response to an analog sinusoidal signal based on the digital sinusoidal signal. The bioimpedance analyzer calculates the bioimpedance based on the target frequency component of the bioelectrical signal. According to the inventive concept, it is possible to improve the selectivity for extracting the target frequency component of the bioelectrical signal and to reduce the area and variations of characteristics for the implementation of the integrated circuit.

A muscle mass estimation method including acquiring a height of a living organism, acquiring an electrical resistance value measured for the living organism, and computing a muscle mass of the living organism using a calculation formula including a first variable including the height of the living organism and the electrical resistance value, and a second variable including the electrical resistance value.

A muscle mass estimation method including acquiring a height of a living organism, acquiring an electrical resistance value measured for the living organism, and computing a muscle mass of the living organism using a calculation formula including a first variable including the height of the living organism and the electrical resistance value, and a second variable including the electrical resistance value.

An electronic device and method are disclosed. The electronic device includes a display, a first sensor, a communication module and a processor. The processor implements the method, including calculating a first impedance via the first biometric information, calculating a first body composition based on the first impedance, receiving second biometric information from an external electronic device, calculating a second impedance using the second biometric information, calculating a second body composition based the second impedance, calculating a total body composition based on at least one of the first impedance and the second impedance, calculating a third body composition for a third part of the body of the user, based on the total body composition, the first body composition, and the second body composition, and displaying at least one of the total body composition, the first body composition, and the second body composition, and the third body composition on the display

Accurately measuring bio-impedance is important for sensing properties of the body. Unfortunately, contact impedances can significantly degrade the accuracy of bio-impedance measurements. To address this issue, a method is provided for estimating an impedance matrix of parasitic network disposed between a first network and a second network of a bio-impedance measurement system, the method comprising determining an impedance matrix for the first network (Z.sub.MUX) based on an impedance matrix for the second network (Z.sub.LOAD) for at least one known load condition; fitting Z.sub.MUX values for Z.sub.LOAD for the at least one known load condition to estimate parameters of the impedance matrix of the intervening network.

A device for determining muscle condition of a region of tissue. The device comprises an electrical impedance myography (EIM) portable probe bearing an electrode array. The electrode array comprises excitation electrodes used to apply multi-frequency electrical signals to the region of tissue and pickup electrodes that are used to collect electrical signals resulting from the application of the multi-frequency electrical signals to the region of tissue. To improve accuracy and reproducibility of EIM measurements, the electrode array is reconfigurable to select different subsets of excitation and pickup electrodes so that the electrodes are oriented differently with respect to muscle fibers. Additional devices may be associated with the EIM probe to measure such parameters as temperature, moisture content of the region, quality of contact of electrodes of the electrode array with a surface of the region and pressure with which the EIM probe is applied to the region. The EIM measurements may be adjusted based on these parameters. Also, ultrasound and electrical impedance tomography measurements may supplement the EIM measurements for more complete analysis of the muscle condition.

A device for determining muscle condition of a region of tissue. The device comprises an electrical impedance myography (EIM) portable probe bearing an electrode array. The electrode array comprises excitation electrodes used to apply multi-frequency electrical signals to the region of tissue and pickup electrodes that are used to collect electrical signals resulting from the application of the multi-frequency electrical signals to the region of tissue. To improve accuracy and reproducibility of EIM measurements, the electrode array is reconfigurable to select different subsets of excitation and pickup electrodes so that the electrodes are oriented differently with respect to muscle fibers. Additional devices may be associated with the EIM probe to measure such parameters as temperature, moisture content of the region, quality of contact of electrodes of the electrode array with a surface of the region and pressure with which the EIM probe is applied to the region. The EIM measurements may be adjusted based on these parameters. Also, ultrasound and electrical impedance tomography measurements may supplement the EIM measurements for more complete analysis of the muscle condition.

Disclosed is a system for evaluating brain trauma via regional changes in tissue impedance. The present disclosure describes a system for non-invasive intracranial monitoring, comprising two or more affecting electrodes arranged between a conductive location of a cranium of a patient and a location on a scalp of the patient, two or more effected electrodes arranged between the conductive location of the cranium of the patient and the location on the scalp of the patient, and processing circuitry configured to apply an electrical stimulus between the two or more affecting electrodes, measure an electrical stimulus differential between the two or more effected electrodes, calculate, for the two or more effected electrodes, a value of an impedance metric, and identify, based on the calculated value of the impedance metric, a health condition of the patient.