JP2006239229A - Body composition meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly precise body composition meter with consideration given to the effect of movement of extracellular fluid. <P>SOLUTION: An impedance measuring part 101 sequentially specifies frequencies of an alternate current generated by a constant current generating circuit 41A and measures whole body impedances and site impedances of at least a single body site for every frequency based on a voltage value obtained by voltage electrodes 11-14 and a current value of the alternate current. A site impedance correction part 102 calculates resistance components of first extracellular fluid and first intracellular fluid of the whole body based on the whole body impedance values for every frequency, calculates resistance components of second extracellular fluid and second intracellular fluid of the body site based on the body site impedance values for every frequency, and corrects the resistance component of the second extracellular fluid based on the correspondence between the resistance components of the first extracellular fluid and the first intracellular fluid. The site impedance for computing the body composition and the body composition are calculated based on the resistance component of the second intracellular fluid and the corrected resistance component of the second extracellular fluid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an impedance measuring apparatus that measures bioelectric impedance, and more particularly to a body composition meter that can measure the body composition of a subject by measuring bioelectric impedance.

Conventionally, a body composition meter that measures the body composition of a subject by measuring bioelectrical impedance (hereinafter simply referred to as “impedance”) has been used for health management of the subject. Moreover, there exists a thing which can divide a test subject's body into a some site | part, can measure the impedance according to site | part, and can calculate a body composition (refer patent documents 1-3).
International Publication No. 2002/043586 Pamphlet JP 2003-290166 A Japanese National Patent Publication No. 10-510455

  According to Patent Documents 1 to 3, since one impedance can be measured for each body part, a more detailed body composition can be measured.

  However, the impedance for each region is greatly affected by the movement of extracellular fluid such as lymph, depending on the time of measurement. However, in Patent Documents 1 to 3, the influence of daily fluctuation due to such movement of extracellular fluid is affected. Not considered.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a highly accurate body composition meter that takes into account the influence of movement of extracellular fluid.

  A body composition meter according to an aspect of the present invention includes a first measurement unit that measures bioelectric impedance of the whole body for each of a plurality of different frequencies, and a left arm, a right arm, a left leg, a right leg for each of the plurality of different frequencies. From the second measuring means for measuring the bioelectric impedance of at least one body part of the trunk and the plurality of whole body bioelectric impedances measured by the first measuring means, the bioelectric impedance of the whole body is calculated. The first calculation means for calculating the plurality of first components to be configured and the bioelectric impedances of the plurality of body parts measured by the second measurement means are used to form a plurality of first components constituting the bioelectric impedance of the body parts. A plurality of second components using at least one component of the second calculation means for calculating the two components, the plurality of first components, and the plurality of second components. And a correction means for correcting the remaining components of the components.

  Preferably, the second measuring unit measures bioelectric impedances of a plurality of different body parts.

  Preferably, each of the constituent component contained in the plurality of first components and the constituent component contained in the plurality of second components is at least one of an extracellular fluid resistance component and an intracellular fluid resistance component. It is a component corresponding to crab.

  Preferably, impedance calculation means for calculating bioelectrical impedance for calculating body composition of the body part from a plurality of components including at least the corrected component corrected by the correction means, and body composition calculated by the impedance calculation means Body composition calculating means for calculating the body composition of the body part from the bioelectrical impedance for calculation is further provided.

  Preferably, the body composition of the body part includes at least one of body fat mass, body fat percentage, lean mass, lean mass, bone mass, muscle mass, and muscle percentage.

  Preferably, the body composition calculation means calculates the body composition of the body part from the bioelectrical impedance for body composition calculation calculated by the impedance calculation means and body specifying information such as age, sex, height and weight. .

  Preferably, a weight measuring means for measuring the weight included in the body specifying information is further provided.

  Preferably, the apparatus further includes display means for displaying the body composition of the body part calculated by the body composition calculation means in association with the body part.

  Preferably, a plurality of electrodes for contacting a plurality of parts of the body, a pair of current electrodes for flowing an alternating current, and a pair of voltage electrodes for measuring voltage are selected. And switching means for switching a plurality of electrodes.

  Preferably, the correction means has a first ratio, which is a ratio of a component corresponding to the resistance component of the extracellular fluid to a component corresponding to the resistance component of the intracellular fluid included in the plurality of first components. Whether the ratio of the component corresponding to the resistance component of the extracellular fluid to the component corresponding to the resistance component of the intracellular fluid included in the plurality of second components is the second ratio. A determination means for determining, and when the determination means determines that the first ratio and the second ratio do not match, the first ratio and the second ratio match, The component corresponding to the resistance component of the extracellular fluid contained in the plurality of second components is corrected.

  Preferably, a plurality of electrodes to be brought into contact with a plurality of predetermined parts of the body of the subject, a pair of current electrodes for flowing an alternating current, and a pair of voltage electrodes for measuring voltage Switching means for switching a plurality of electrodes, a generating means for generating a plurality of alternating currents of different frequencies according to instructions, and a frequency of the alternating current generated by the generating means. Based on the designating means for sequentially designating, the voltage value obtained from the voltage electrode and the current value of the alternating current, the whole body impedance and the first part-specific impedance of at least one body part are measured for each frequency. And the first part-specific impedance based on the whole-body impedance for each frequency measured by the measurement means and the first part-specific impedance. And a correcting means for. Such a correction means calculates the resistance component of the first extracellular fluid and the resistance component of the first intracellular fluid in the whole body based on the value of the whole body impedance for each frequency measured by the measurement means. The resistance component of the second extracellular fluid and the resistance component of the second intracellular fluid in the body part are calculated based on the first calculation means and the value of the impedance by part for each frequency measured by the measurement means. Second calculating means, and second calculating means based on the correspondence relationship between the resistance component of the first extracellular fluid and the resistance component of the first intracellular fluid calculated by the first calculating means. A correction means for correcting the resistance component of the second extracellular fluid calculated in step 2; a resistance component of the second intracellular fluid calculated by the second calculation means; and a second after correction by the correction means. Based on the resistance component of the extracellular fluid and by body part calculation And a third calculation means for calculating the impedance. Furthermore, the first calculation means for calculating the body composition by body part according to the part impedance for body composition calculation calculated by the third calculation means and the body specifying information of the subject is provided. .

  According to the present invention, by correcting the resistance component of the extracellular fluid in the body part, it is possible to correct the daily fluctuation of the site-specific impedance due to the influence of the movement of the extracellular fluid. Thereby, a highly accurate body composition can be calculated.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Appearance and Configuration of Body Composition Meter in Embodiment of the Present Invention>
FIG. 1 is an external perspective view of a body composition meter 100 according to an embodiment of the present invention.

  Referring to FIG. 1, body composition meter 100 is constituted by a first housing 1 and a second housing 2. The first housing 1 and the second housing 2 are connected by a cable 3. The body composition meter 100 is provided with a plurality of electrodes 11 to 18 that are brought into contact with a plurality of predetermined parts of the body of the subject.

  The first housing 1 has a placement part 1.1 for placing the subject's left foot, a placement part 1.2 for placing the subject's right foot, and a second housing 2. A storage portion 4 for storing the cable 3 is provided. It is assumed that a weight measuring unit 32 (see FIG. 3) for measuring the weight of the subject, for example, a weight sensor is provided inside the first housing 1.

  The placement units 1.1 and 1.2 are each provided with two electrodes for contacting the soles of the subjects. The left foot placement section 1.1 is provided with an electrode 17 for current application on the finger side of the left foot, and an electrode 13 for voltage measurement on the heel side of the left foot. Similarly, the right foot placement portion 1.2 is provided with an electrode 18 for current application on the finger side of the right foot and an electrode 14 for voltage measurement on the heel side of the left foot.

  In addition, the placement portions 1.1 and 1.2 are formed so as to have a substantially outer shape of the foot so that the subject comes into contact with the electrodes 13, 14, 17, 18 when both feet are placed. As a result, even if the soles of the feet deviate from the placement portions 1.1 and 1.2 in the left-right direction, it is difficult to deviate from the electrodes 17 and 18 for current application and the electrodes 13 and 14 for voltage measurement. It is possible to prevent the occurrence of errors due to fluctuations in the contact area. Moreover, the influence by the fluctuation | variation of the contact state in a thigh can also be prevented. Therefore, highly reliable measurement is possible.

  The second housing 2 is composed of a main body part 2.1, a left hand grip part 2.2 for a subject to hold with a left hand, and a right hand grip part 2.3 for a subject to hold with a right hand. Is done.

  On the front surface of the main body 2.1, there are provided a display unit 20 for displaying measurement results and various information, and an operation unit 30 that is operated by the subject and receives instructions and input of various information from the subject. It is done. In addition, the display part 20 and the operation part 30 provided in the main-body part 2.1 of the 2nd housing | casing 2 are demonstrated in detail later using FIG.

  In the present embodiment, the power switch 301 included in the operation unit 30 is provided, for example, in the center of the front surface of the first housing 1.

  The grips 2.2 and 2.3 of the second housing 2 are each provided with two electrodes for contacting the inside of the subject's hand. In the grip part 2.2 for the left hand, an electrode 15 for current application is provided on the thumb side of the left hand, and an electrode 11 for voltage measurement is provided on the little finger side of the left hand. Similarly, in the grip part 2.3 for the right hand, an electrode 16 for current application is provided on the thumb side of the right hand, and an electrode 12 for voltage measurement is provided on the little finger side of the right hand.

  As described above, body composition monitor 100 according to the embodiment of the present invention is configured such that electrodes for current application and voltage measurement are brought into contact with the four parts of the left hand, right hand, left foot, and right foot, respectively. In addition, it is not restricted to such a structure, For example, it is good also as providing the electrode for the electric current application for another site | part, and a voltage measurement.

  FIG. 2 is a diagram showing a measurement posture when a subject measures body composition using body composition meter 100 according to the embodiment of the present invention.

  Referring to FIG. 2, subject 200 places left foot 203 and right foot 204 on placement portions 1.1 and 1.2 of first housing 1 in an upright posture, respectively. The left hand 201 holds the grip portion 2.2 of the second housing, and the right hand 202 holds the grip portion 2.3. At this time, the elbows of both arms 205 and 206 are extended, and the second housing 2 is held at a substantially shoulder height so as to face the front of the body, so that the arms 205 and 206 and the torso 207 form a substantially right angle. To.

  FIG. 3 is a block diagram of body composition monitor 100 in the embodiment of the present invention. Referring to FIG. 3, body composition monitor 100 includes a plurality of electrodes 11 to 18, display unit 20, operation unit 30, and body weight measurement unit 32, and controls body composition meter 100 as a whole and performs various calculations. A microcomputer 10 for performing processing, a constant current generating circuit 41A for generating AC constant currents having a plurality of different frequencies, and a current application for switching the current application electrodes 15-18. The electrode switching circuit 42, the voltage measurement electrode switching circuit 43 for switching the voltage measurement electrodes 11 to 14, the voltage information obtained from the voltage measurement electrode switching circuit 43 and the weight information obtained from the weight measurement unit 32. In order to switch the input to either one, the input switching circuit 44 and the voltage information and weight information obtained from the input switching circuit 44 are converted from an analog signal to a digital signal. A (analog) / D (digital) conversion circuit 45, a power supply unit 31 for supplying power to the microcomputer 10 by operating a power switch 301 included in the operation unit 30, and information such as measurement results And an external memory 33 for storing. Further, the microcomputer 10 includes an internal memory 133 for storing various control programs.

  In the present embodiment, the external memory 33 includes, for example, an EEPROM (Electrically Erasable Programmable Read-Only Memory), and the measurement results such as the body identification information of the subject and the body composition, which will be described in detail later, Stored in EEPROM.

  Here, the “body specifying information” is the body information of the subject that is required when calculating the body composition of the whole body and each part of the subject in the embodiment of the present invention.

  The “body-specific information” necessary for calculating the body composition of the whole body is at least height and weight information, and more preferably information including age and sex in addition to height and weight. Further, the “body-specific information” required when calculating the body composition for each part is at least the height or the axial length and weight information of each body part, and more preferably the height or each body part. In addition to the length and weight in the axial direction, the information includes age and sex.

  In the description here, the “body-specific information” necessary for calculating the body composition for the whole body and each part refers to four body information such as height, weight, age, and sex.

  The body composition meter 100 can measure the body weight in the body specifying information in the body weight measurement unit 32. Therefore, at the time of body composition measurement, in the present embodiment, other three body information (height, age, sex) is input in advance by the subject using the operation unit 30.

  The body composition meter 100 may be configured not to include the weight measuring unit 32. In this case, the above four pieces of body information (height, weight, age, and sex) are input by the operation unit 30 in advance. And

  Note that “by part” indicates that each part of the body is divided. In the present embodiment, the whole body is divided into five body parts: left arm, right arm, left leg, right leg, and trunk. Therefore, the body composition of five body parts, that is, the left arm, the right arm, the left leg, the right leg, and the trunk is measured as the body composition for each part. Here, “left arm” and “right arm” are body parts representing, for example, from the wrist to the shoulder of each arm, and “left leg” and “right leg” are, for example, from the ankle of each leg to the base of the leg. It is assumed that the “trunk” is a body part representing the trunk.

  In the present embodiment, the “systemic body composition” is at least one of the whole body lean mass and body fat percentage, and more preferably the whole body lean mass and body fat percentage, Biometric information including the muscle mass, muscle percentage, visceral fat level, and the like.

  The “body composition by region” is at least one of the lean body mass and body fat percentage for each body part, and more preferably, in addition to the lean body mass and body fat percentage for each body part, It is biometric information including the muscle mass and muscle ratio of each.

  Hereinafter, the whole body and the above five body parts, which are the targets of body composition measurement, are collectively referred to as “measurement parts”.

  The microcomputer 10 includes an impedance measurement unit 101, a part-specific impedance correction unit 102, and a body composition calculation unit 103, and according to a program stored in the internal memory 133, impedance measurement, part-specific impedance correction, and body composition Perform the calculation. The site-specific impedance correction unit 102 includes a component calculation unit 1021, a component correction unit 1022, and an impedance calculation unit 1022. These processes executed by the microcomputer 10 will be described in detail later.

  Further, the microcomputer 10 measures the body weight by a known method based on a signal from the weight measuring unit 32 acquired through the A / D conversion circuit 45, for example, a weight sensor. In addition, a signal for displaying a measurement result in a body composition calculation unit 103 described later on the display unit 20 is generated. Further, writing to and reading from the external memory 33 are performed.

  The constant current generation circuit 41A can output alternating currents having a plurality of different frequencies in response to an instruction from the microcomputer 10. For example, the constant current generating circuit 41A may be capable of changing the frequency to be generated in accordance with an instruction from the microcomputer 10, or may include a plurality of circuits capable of generating a predetermined frequency.

  Next, the specific example of the display part 20 and the operation part 30 of the body composition monitor 100 in embodiment of this invention is shown in FIG. FIG. 4 is a front view of the second housing 2.

  Referring to FIG. 4, display unit 20 of body portion 2.1 of second housing 2 includes a first display region 20.1 and a second display region 20.2. The first display area 20.1 and the second display area 20.2 are made of, for example, liquid crystal.

  In the first display area 20.1, numerical values, characters, figures and the like indicating the body specifying information and measurement results of the subject are displayed. In the second display area 20.2, for example, a figure (hereinafter referred to as “human body diagram”) in which the body is divided into a plurality of body parts is displayed. And when a measurement result is displayed on the 1st display area 20.1, the part of the to-be-measured site | part being displayed is lit-up display among a human body figure. Thereby, it is possible to inform the subject of information on the measurement site displayed in the first display area 20.1.

  In addition, the display part 20 is not restricted to such a structure, What is necessary is just to be able to inform a test subject of the information of the to-be-measured site | part being displayed.

  The operation unit 30 includes a plurality of operation switches. For example, a whole body switch 302 for displaying a measurement result such as a whole body composition, a trunk switch 303 for displaying a measurement result such as a body composition of a trunk, and a leg including a left leg and a right leg Leg switch 304 for displaying measurement results such as body composition, arm switch 305 for displaying measurement results such as body composition of the arm part including the left and right arms, and settings for performing various settings and display switching / Display switch 306, a memory switch 307 for displaying the measurement result stored in the external memory 33, an up / down switch 308 for increasing / decreasing a numerical value when setting part information, and information on the subject And a personal number switch 309 for specifying. Note that the whole body switch 302, the trunk switch 303, the leg switch 304, and the arm switch 305 are collectively referred to as “part-specific switches”.

  At least one personal number switch 309 is provided. In FIG. 4, two are provided, and for each number (1, 2) designated by the personal number switch 309, the subject's body specifying information and measurement results are stored in the external memory 33.

  Note that, for example, a guest switch 310 may be provided in the operation unit 30, and body specific information of the subject may be input for each measurement to measure the body composition.

  Further, the operation unit 30 may not be configured by the operation switches as described above. For example, various information and instructions may be input using a touch panel or the like.

<Diurnal variation in impedance by region>
FIG. 5 is a schematic diagram showing impedance components of each body part. FIG. 6 is a schematic diagram showing impedance components of the whole body. FIG. 5 and FIG. 6 show each body part and whole body of the subject's body approximated by an equivalent circuit composed of a resistor and a capacitor.

  Here, the components of each impedance are resistance due to intracellular fluid (hereinafter referred to as “resistance component of intracellular fluid”) Ri, resistance due to extracellular fluid (hereinafter referred to as “resistance component of extracellular fluid”) Ro, capacitance due to cell membrane. (Hereinafter referred to as “capacitance component of cell membrane”) Ci. At this time, each impedance is represented by an equivalent circuit in which the capacitance component Ci of the cell membrane, the resistance component Ri of the intracellular fluid, and the resistance component Ro of the extracellular fluid are connected in parallel.

  Referring to FIG. 5, the left arm impedance is “Zlh”, the right arm impedance is “Zrh”, the trunk impedance is “Zt”, the left leg impedance is “Zlf”, and the right leg impedance is “Zrh”. It expresses. Further, referring to FIG. 6, the impedance of the whole body is expressed as “Zw”. Further, in the following description, the arm impedance including the left arm impedance Zlh and the right arm impedance Zrh is “Zh”, and the leg impedance including the left leg impedance Zlf and the right leg impedance Zrf is “Zf”. .

  Referring to FIG. 5, impedance Zlh of the left arm is represented by an equivalent circuit of a capacitance component Ci_lh of the cell membrane, a resistance component Ri_lh of the intracellular fluid, and a resistance component Ro_lh of the extracellular fluid. The impedance Zrh of the right arm is represented by an equivalent circuit of the capacitance component Ci_rh of the cell membrane, the resistance component Ri_rh of the intracellular fluid, and the resistance component Ro_rh of the extracellular fluid. The trunk impedance Zt is represented by an equivalent circuit of the capacitance component Ci_t of the cell membrane, the resistance component Ri_t of the intracellular fluid, and the resistance component Ro_t of the extracellular fluid. The impedance Zlf of the left leg is represented by an equivalent circuit of a capacitance component Ci_lf of the cell membrane, a resistance component Ri_lf of the intracellular fluid, and a resistance component Ro_lf of the extracellular fluid. The impedance Zrf of the right leg is represented by an equivalent circuit of the capacitance component Ci_rf of the cell membrane, the resistance component Ri_rf of the intracellular fluid, and the resistance component Ro_rf of the extracellular fluid.

  Referring to FIG. 6, the whole body impedance Zw is expressed by an equivalent circuit of a capacitive component Ci_w of the cell membrane, a resistance component Ri_w of the intracellular fluid, and a resistance component Ro_w of the extracellular fluid.

  Among the impedance components, body water such as lymph fluid corresponding to the resistance component Ro of the extracellular fluid generally moves to the lower body during the day from morning to evening. Such daily fluctuations of the impedance by region due to the influence of the movement of body moisture will be described with reference to FIG.

  FIG. 9 is a diagram for explaining the daily fluctuation of the impedance by region. In FIG. 9, the horizontal axis represents time and the vertical axis represents impedance value (Ω). FIG. 9 shows an example in which the user wakes up at 8 am and goes to bed at 24:00. Each impedance shown here is assumed to be an impedance measured at a commonly used predetermined frequency (for example, 50 kHz).

  As shown in FIG. 9, the whole body impedance Zw is constant (for example, 300Ω) without being subject to daily fluctuations due to the influence of body water movement. This is because, as shown in FIG. 8, the whole body is not divided into parts and regarded as one resistance, and the whole body impedance Zw is obtained, so that the overall impedance does not change even if the body moisture distribution changes.

  On the other hand, the impedance Zh of the arm (upper limb) gradually increases with time from 8 o'clock to 24 o'clock. In FIG. 9, 350Ω is measured at 8 o'clock and 370Ω is measured at 24 o'clock. This is because body moisture decreases and resistance increases with time.

  On the other hand, the impedance Zf of the leg (lower limb) gradually decreases with time from 8 o'clock to 24 o'clock. In FIG. 9, 330Ω is measured at 8 o'clock and 310Ω is measured at 24 o'clock. This is because body moisture increases and resistance decreases with time.

  Thus, it can be said that the whole body impedance Zw does not change within the day due to the influence of the movement of body moisture unless there is a special event such as a large amount of sweat in the sauna. However, as shown in FIG. 9, the impedance for each part is affected by the movement of body moisture, and the daily fluctuation occurs.

  For this reason, when the body composition for each region is calculated using the measured impedance for each region as it is, the body composition for each region also varies depending on the time measured in one day. For example, the body fat percentage of the arms (upper limbs) and legs (lower limbs) will vary by about 1 to 2% depending on the measurement time. If it does so, the body composition according to an appropriate site | part cannot be shown to a test subject.

  In view of this, the body composition meter 100 according to the embodiment of the present invention corrects the movement of the daily fluctuation due to the movement of the body moisture and measures the body composition for each region with high accuracy.

<Measurement of impedance in the embodiment of the present invention>
The impedance measuring unit 101 measures site-specific impedances of the whole body and at least one body part. In the present embodiment, the impedances of the five body parts such as the left arm, the right arm, the left leg, the right leg, and the trunk are measured as the impedance for each part. Of these five body parts, for example, the impedance of two body parts such as the left arm and the left leg may be measured, or the impedance of a plurality of body parts by other combinations may be measured. Good.

  In the present embodiment, the impedance measurement unit 101 first measures the left arm impedance Zlh and the right arm impedance Zrh. Then, for example, the impedance Zh of the arm is obtained by combining the impedance Zlh of the left arm and the impedance Zrh of the right arm.

  Also, the left leg impedance Zlf and the right leg impedance Zrf are measured. Then, for example, the impedance Zf of the leg is obtained by combining the impedance Zlf of the left leg and the impedance Zrf of the right leg.

  In the following description, the whole body and five body parts (left arm, right arm, left leg, right leg, and trunk), which are impedance measurement targets, are collectively referred to as “measurement parts”.

  By the way, as shown in FIG. 5 and FIG. 6, the impedance of the measurement site is a composite component of the resistance component Ro of the extracellular fluid, the resistance component Ri of the intracellular fluid, and the capacitance component Ci of the cell membrane.

  As described above, the resistance component Ro of extracellular fluid throughout the body generally does not vary substantially throughout the day. On the other hand, the resistance component Ro of the extracellular fluid in the body part varies, for example, in the morning and evening even within the same day. Further, in the short term, the volume component Ci of the cell membrane and the resistance component Ri of the intracellular fluid hardly vary in the whole body and the body part. Therefore, for example, when the body composition is measured in the morning and evening in one day, the body composition of the whole body does not substantially change, but only the body composition of each region changes.

  From this, it is understood that the resistance component Ro of the extracellular fluid for each region needs to be corrected in order to accurately measure the body composition for each region.

  The impedance measuring unit 101 in the present embodiment specifies the frequency of the alternating current generated in the constant current generating circuit 41A that can generate a plurality of different frequencies. “Several different frequencies” are at least three different frequencies. Such at least three different frequencies can be calculated by separating the impedance components (extracellular fluid resistance component Ro, intracellular fluid resistance component Ri, cell membrane capacitance component Ci) from the measured impedance. It is a frequency to do.

  In the present embodiment, three types of frequencies Fa, Fb, and Fc are generated in the constant current generation circuit 41A. That is, the impedance measuring unit 101 sequentially designates the frequency generated by the constant current generating circuit 41A from the above three types of frequencies, and measures the impedance of the whole body and each part for each designated frequency. The frequency Fa can be set to 50 kHz, the frequency Fb can be set to 100 kHz, and the frequency Fc can be set to 10 kHz, for example. In the present embodiment, the above three types of frequencies are used as a plurality of different frequencies, but it is sufficient that at least the resistance component Ro of the extracellular fluid and the resistance component Ri of the intracellular fluid can be extracted. Therefore, there may be two types of frequencies or more than three types.

  Next, a specific impedance measurement method will be described.

  The impedance measuring unit 101 controls the current application electrode switching circuit 42 and the voltage measurement electrode switching circuit 43 to provide a current application pair of electrodes 15 to 18 and a voltage measurement pair of electrodes 11 to 14, respectively. By sequentially switching, impedances (Zw, Zlh, Zrh, Zt, Zlf, Zrh) by whole body and region are measured. More specifically, each impedance is measured based on the current value supplied from the constant current generation circuit 41 </ b> A and the potential difference between the two electrodes acquired via the A / D conversion circuit 45.

  For example, the impedance Zlh of the left arm is measured by passing an alternating current between the left hand and the left foot and measuring the potential difference between both hands, as shown in FIG. More specifically, the impedance measuring unit 101 causes an alternating current of each frequency Fa, Fb, Fc to flow between the current application electrodes 15, 17 and measures a potential difference between the voltage measurement electrodes 11, 12. Three types of impedance Zlh of the left arm are measured.

  Further, in order to measure the impedance Zw of the whole body, as shown in FIG. 8, it is measured by passing an alternating current between both hands and both feet and measuring the potential difference between both hands and both feet. More specifically, the impedance measuring unit 101 connects the current application electrodes 15 and 16 of both hands and the current application electrodes 17 and 18 of both feet, and the voltage measurement electrode 11 of both hands. 12 and between the electrodes 13 and 14 for voltage measurement of both legs, respectively, and an alternating current of each frequency Fa, Fb, Fc is passed in one direction through the current application electrodes 15 to 18 for voltage measurement. The three types of impedance Zw of the whole body are measured by measuring a potential difference using the electrodes 11-14.

  In the present embodiment, as described above, the component constituting the impedance of the measurement site includes the capacitive component Ci of the cell membrane, the resistance component Ri of the intracellular fluid, and the resistance component Ro of the extracellular fluid. Although there are three, it may be composed of other components.

<Correction of impedance by region>
The site-specific impedance correction unit 102 corrects the site-specific impedance based on the whole body impedance and the site-specific impedance measured by the impedance measurement unit 101 for each frequency. In the following description, the part-specific impedance for body composition calculation calculated by the impedance calculation unit 1023 in the part-specific impedance correction unit 102 is referred to as “calculation part-specific impedance”.

  First, an example of an impedance component calculation method executed by the component calculation unit 1021 of the site-specific impedance correction unit 102 will be described.

  The component calculation unit 1021 calculates at least the resistance component Ro of the extracellular fluid and the resistance component Ri of the intracellular fluid based on the frequency value and the impedance value for each frequency for each measurement site.

  Specifically, for example, it can be calculated using the following equation. In the following expression, | Z | is an impedance value measured for each frequency, and f indicates the frequency of the alternating current.

Zr = [Ro {Ri (Ro + Ri) + Xc ² }] / {(Ro + Ri) ² + Xc ² }
... (5)
Zi = (Ro ² × Xc) / {(Ro + Ri) ² + Xc ² } (6)
Xc = 1 / (j × 2π × f × Ci) (7)
Using the equations (4) to (7), the resistance component Ro of the extracellular fluid and the resistance component Ri of the intracellular fluid can be calculated for each site to be measured.

  As described above, when the resistance component Ro of the extracellular fluid and the resistance component Ri of the intracellular fluid are calculated for each measurement site, the constituent component correction unit 1022 of the site-specific impedance correction unit 102 calculates the intracellular fluid in the body site. The resistance component of the extracellular fluid in the body part so that the ratio of the resistance component Ro_b of the extracellular fluid to the resistance component Ri_b of the extracellular fluid matches the ratio of the resistance component Ro_w of the extracellular fluid to the resistance component Ri_w of the whole body Correct the value of Ro_b.

  The “extracellular fluid resistance component Ro_b” is a general term for the extracellular fluid resistance component (eg, Ro_lh) for each body part, and the “intracellular fluid resistance component Ri_b” It is a general term for resistance components (for example, Ri_lh) of intracellular fluid for each part.

  As described above, in the embodiment of the present invention, the constituent component correcting unit 1022 includes the resistance component Ri_w of the intracellular fluid and the resistance component Ro_w of the extracellular fluid that constitute the impedance of the whole body, and the cells that constitute the impedance of the body part. The resistance component Ro_b of the extracellular fluid is corrected using the resistance component Ri_b of the internal fluid. If the component constituting the impedance of the measurement site is a component different from the capacitance component Ci of the cell membrane, the resistance component Ri of the intracellular fluid, and the resistance component Ro of the extracellular fluid, The remaining components constituting the impedance of the body part are corrected using the plurality of components constituting and the at least one component constituting the impedance of the body part. This “remaining component” is preferably a component corresponding to the resistance component Ro_b of the extracellular fluid.

  When the value of the resistance component Ro_b of the extracellular fluid is corrected by the component correction unit 1022, the impedance calculation unit 1023 of the site-specific impedance correction unit 102 calculates the site-specific impedance for calculation.

  The specific process executed by the site-specific impedance correction unit 102 will be described later with reference to the flowchart of FIG.

<Calculation of body composition>
The body composition calculation unit 103 calculates the body composition for each part of the subject based on the impedance for each part measured by the impedance measurement part 101 or the information for the impedance for each part for calculation calculated by the impedance calculation part 1023. . The body composition calculation unit 103 calculates the body composition of the whole body of the subject based on the information on the whole body impedance measured by the impedance measurement unit 101 at the frequency Fa, for example.

  Here, of the whole body and region-specific body compositions calculated by the body composition calculation unit 103, a method for calculating a lean mass and a body fat percentage will be described.

(Calculation of lean mass)
First, a formula for calculating a lean mass is expressed by the following formula (1), where FFM is FFM, impedance is Z, height is H, weight is W, and age is Ag. The impedance “Z” here is a calculated value when the impedance calculation unit 1023 calculates the impedance for each part for calculation.

FFM = a · H ² / Z + b · W + c · Ag + d (1)
In the above formula (1), a to d are predetermined constants, and are different for each sex and each site to be measured. Therefore, when calculating the lean mass (FFM), the value of the impedance “Z” in equation (1) is “Zw” if the measured site is the whole body, and “Zt” if the measured site is the trunk. It becomes the value of.

  Predetermined constants a to d used in the formula for calculating the lean mass for each sex and each measurement site are stored in the external memory 33 in advance. Note that the formula for calculating the lean mass (FFM) is not limited to the linear function as in the expression (1), and may be a quadratic function or the like.

(Calculation of body fat percentage)
The formula for calculating the body fat percentage of the whole body is expressed by the following formula (2).

Body fat percentage (%) = {body fat mass (kg) ÷ body weight (kg)} × 100 (2)
The formula for calculating the body fat mass is represented by the following formula (3).

Body fat mass (kg) = body weight (kg) -lean body mass (kg) (3)
Thus, the whole body fat percentage is calculated based on the whole body lean mass (FFM) calculated by the above equation (1).

  The body fat percentage for each part is calculated based on the correlation with the reference measured in advance by DEXA (Dual Energy X-ray Absorptiometry) from the information of the measured impedance for each part and the body specifying information. .

  The body composition calculation unit 103 calculates the body composition of the five body parts, the left arm, the right arm, the left foot, the right leg, and the trunk, as the body composition for each part. The body composition of three body parts of the trunk may be calculated.

  In addition, biometric information other than lean mass and body fat percentage in the body composition can be calculated using, for example, a known method.

<Operation of Body Composition Monitor in the Embodiment of the Present Invention>
FIG. 10 and FIG. 11 are flowcharts showing the flow of the measurement process of body composition monitor 100 in the embodiment of the present invention. Note that at the time when this process is disclosed, it is assumed that the body specific information of the subject is stored in advance in the external memory 33 in association with the personal number of the subject.

  Referring to FIG. 10, first, when power switch 301 is operated, power is supplied to microcomputer 10 by power supply unit 31 (step S10). Subsequently, the microcomputer 10 initializes the weight scale in the weight measurement unit 32 (step S12).

  And the microcomputer 10 judges whether the output of the sensor signal from the weight measurement part 32 was stabilized (step S14). If it is determined that the output of the sensor signal is not stable (NO in step S14), the process returns to step S12. On the other hand, when it is determined that the output of the sensor signal is stable (YES in step S14), the microcomputer 10 detects that preparation for weight measurement is completed (step S16).

  Subsequently, the microcomputer 10 determines whether or not a personal number has been selected (step S18). If it is determined that no personal number has been selected (NO in step S18), it is determined that the measurement mode is only for weight (step S20).

  Subsequently, the microcomputer 10 determines whether or not the weight value is stabilized within a predetermined time (step S22). If the weight value does not stabilize within the predetermined time (NO in step S22), it is determined that there is an error (step S24). At this time, a display indicating an error may be displayed in the first display area 20.1 of the display unit 20. In the subsequent steps, if it is determined that an error has occurred, the same display may be performed.

  When the process of step S24 ends, the body composition analyzer 100 is turned off and the measurement process ends (step S68).

  If it is determined in step S22 that the weight value has stabilized within a predetermined time (YES in step S22), the weight value is determined (step S26). Then, the microcomputer 10 displays the weight value determined in step S26 on the display unit 20 (step S28). When the process of step S28 ends, the body composition analyzer 100 is turned off and the measurement process ends (step S68).

  On the other hand, if it is determined in step S18 that a personal number has been selected (YES in step S18), it is then determined whether or not the memory switch 307 has been pressed (step S30). If it is determined that the memory switch 307 has been pressed (YES in step S30), the memory value indicating the past measurement result stored in the external memory 33 is displayed (step S32). When past memory values are not stored in the external memory 33, such as when body composition is measured for the first time, for example, an error display may be performed and the process may proceed to step S34.

  When the process of step S32 is completed, the body composition analyzer 100 is turned off and the measurement process is terminated (step S68).

  On the other hand, when it is determined in step S30 that the memory switch 307 has not been pressed (NO in step S30), the microcomputer 10 determines that it is in the body weight and body composition measurement mode (step S34). Then, the microcomputer 10 determines whether or not the weight value is stabilized within a predetermined time (step S36). If the weight value is not stabilized within the predetermined time (NO in step S36), the microcomputer 10 determines that there is an error (step S38). When the process of step S38 is completed, the body composition meter 100 is turned off and the measurement process is terminated (step S68).

  If it is determined in step S36 that the weight value has stabilized within a predetermined time (YES in step S36), the microcomputer 10 determines the weight value (step S40). The determined weight value is temporarily stored in a predetermined area of the external memory 33, for example.

  When the process of step S40 is completed, the microcomputer 10 transmits a control signal to the input switching circuit 44, switches the input to the voltage information from the voltage measurement electrodes 11 to 14, and advances the process to step S42 shown in FIG. .

  Referring to FIG. 11, in step S42, impedance measurement unit 101 of microcomputer 10 performs an impedance measurement process. The impedance measurement process in step S42 is shown in FIG.

  FIG. 12 is a diagram showing a flow of impedance measurement processing in the embodiment of the present invention.

  Referring to FIG. 12, first, impedance measurement unit 101 designates frequency Fa as a frequency to be generated in constant current generation circuit 41A (step S102).

  Next, the impedance measuring unit 101 measures the whole body impedance at the designated frequency (step S104). Subsequently, the impedance measuring unit 101 measures the impedance for each body part at the designated frequency (step S106). In addition, each impedance measured by step S104 and step S106 is temporarily memorize | stored in the predetermined area | region of the external memory 33, for example.

  When the process of step S106 is completed, the impedance measuring unit 101 determines whether or not the impedance at the frequency Fb has been measured (step S108).

  If it is determined that the impedance at frequency Fb is not measured (NO in step S108), the frequency generated in constant current generating circuit 41A is changed to frequency Fb (step S110). Then, when the process of step S110 ends, the process returns to step S104.

  On the other hand, when it is determined that the impedance at the frequency Fb has been measured (YES in step S108), the impedance measuring unit 101 determines whether the impedance at the frequency Fc has been measured (step S112).

  If it is determined in step S112 that the impedance at the frequency Fc is not measured (NO in step S112), the frequency generated in the constant current generating circuit 41A is changed to the frequency Fc (step S114). Then, when the process of step S114 ends, the process returns to step S104.

  On the other hand, when it is determined that the impedance at frequency Fc has been measured (YES in step S112), the impedance measurement process is terminated.

  Note that the frequency designation order is not limited to the above order. Further, for example, after obtaining the whole body impedance for each of the frequencies Fa, Fb, and Fc, the impedance for each part for each body part for each of the frequencies Fa, Fb, and Fc may be obtained.

  Further, each impedance may be measured as follows. First, after flowing an alternating current, it is determined whether or not the impedance value is within a predetermined range within a predetermined time. If the impedance value does not fall within a predetermined range within a predetermined time, it is determined that an error has occurred. On the other hand, when it is determined that the impedance value is within the predetermined range within the predetermined time, it is subsequently determined whether or not the impedance value is stabilized within the predetermined time. If the impedance value does not stabilize within a predetermined time, it is determined that an error has occurred. When it is determined that the impedance value is stable within a predetermined time, the value is set as a measured value of impedance.

  Returning to FIG. 11 again, when the impedance measurement process in step S42 is completed, the site-specific impedance correction unit 102 in the microcomputer 10 performs site-specific impedance correction processing. The site-specific impedance correction processing in step S50 is shown in FIG.

  FIG. 13 is a flowchart showing the flow of the site-specific impedance correction processing in the embodiment of the present invention. The processing shown below is performed by any one of the component calculation unit 1021, the component correction unit 1022, and the impedance calculation unit 1023 of the site-specific impedance correction unit 102. The description will be made assuming that it is executed by the unit 102.

  Referring to FIG. 13, first, site-specific impedance correction unit 102 calculates whole body extracellular fluid resistance component Ro_w and intracellular fluid resistance component Ri_w using, for example, the equations (4) to (7) above. Calculate (step S202). Next, the site-specific impedance correction unit 102 calculates the resistance component Ro_b of the extracellular fluid and the resistance component Ri_b of the intracellular fluid for each body site using, for example, the equations (4) to (7) (steps). S204).

  Next, the part-specific impedance correction unit 102 selects one body part among the plurality of body parts measured by the impedance measurement unit 101 (step S206). Then, D = (Ro_b / Ri_b) / (Ro_w / Ri_w) is calculated for each selected body part (step S208). That is, the comparison value “D” of the ratio of the resistance component Ro_w of the extracellular fluid to the resistance component Ri_w of the intracellular fluid in the whole body with respect to the ratio of the resistance component Ro_b of the extracellular fluid to the resistance component Ri_b of the intracellular fluid in the body part. calculate.

  Subsequently, the part-specific impedance correction unit 102 determines whether or not the comparison value D = 1 of the selected body part (step S210). That is, the ratio of the resistance component Ro_b of the extracellular fluid to the resistance component Ri_b of the intracellular fluid of the selected body part matches the ratio of the resistance component Ro_w of the extracellular fluid to the resistance component Ri_w of the intracellular fluid throughout the body. Determine whether or not.

  If it is determined in step S210 that comparison value D = 1 (YES in step S210), the process proceeds to step S214.

  On the other hand, if it is determined in step S210 that the comparison value D is not 1, the resistance component Ro_b of the extracellular fluid of the selected body part is corrected (step S212). Specifically, it is corrected as follows.

Ro′_b = Ro_b / D
In the above formula, “Ro′_b” is the resistance component of the extracellular fluid after correction.

  Thereby, the resistance component Ro_b of the extracellular fluid in the selected body part is corrected so as to coincide with the ratio of the resistance component Ro_w of the extracellular fluid to the resistance component Ri_w of the intracellular fluid in the whole body.

  When the resistance component Ro′_b of the extracellular fluid is calculated in step S212, the process proceeds to step S214.

  In step S214, the site-specific impedance correction unit 102 calculates the site-specific impedance for calculation. When the resistance component Ro_b of the extracellular fluid is corrected in step S212, the impedance for each part for calculation is calculated using the resistance component Ro'_b of the corrected extracellular fluid. Specifically, the impedance for each part for calculation (denoted as “| Z ′ |”) is calculated by applying the formulas (4) to (7), for example.

  If the process of step S212 has not been performed, the impedance for each region for calculation is calculated using the resistance component Ro_b of the extracellular fluid calculated in step S204. Alternatively, the site-specific impedance calculated at the frequency Fa may be used as the site-specific impedance for calculation.

  When the process of step S214 ends, the process proceeds to step S216.

  In step S216, the part-specific impedance correction unit 102 determines whether all body parts have been selected. If it is determined that not all body parts have been selected (NO in step S216), the process returns to step S206 and the above-described processing is repeated. On the other hand, when it is determined that all the body parts have been selected (YES in step S216), the part-specific impedance correction process is terminated.

  In step S210, it is determined whether or not the comparison value D is 1. However, with a predetermined tolerance, the ratio of the resistance component Ro_b of the extracellular fluid to the resistance component Ri_b of the intracellular fluid in the body part is It may be determined whether or not the degree of coincidence with the ratio of the resistance component Ro_w of the extracellular fluid to the resistance component Ri_w of the extracellular fluid in the whole body is within an allowable range.

  In the present embodiment, all body parts (left arm, right arm, trunk, left leg, right leg) are targeted for impedance correction processing for each part, but only predetermined body parts may be targeted. .

  Returning again to FIG. 11, when the impedance correction process for each part in step S50 is completed, the impedance for the body composition calculation is determined (step S52). In step S52, the whole body impedance Zw at the frequency Fa measured by the impedance measurement unit 101 and the calculation site-specific impedance (| Z ′ |) calculated by the site-specific impedance correction unit 102 are impedance for body composition calculation. As a value.

  In the present embodiment, the impedance values determined in step S52 are the impedance values of the whole body and three body parts (arm part, trunk part, leg part). That is, the impedance values of the left arm and the right arm are combined to obtain the impedance value of the arm portion, and the impedance values of the left leg and the right leg are combined to obtain the impedance value of the leg portion.

  When the impedance value for the body composition calculation is determined in step S52, the body composition calculation unit 103 performs a body composition calculation process (step S54). In step S54, the body composition calculation unit 103 calculates the body composition of the whole body and the body composition for each part as described above. The calculation of the body composition can be performed by a known method, for example.

  When the process of step S54 ends, the microcomputer 10 stores the weight value determined in step S40 and the numerical value of the body composition calculated in step S54 in the external memory 33 as a measurement result (step S56).

  For example, a predetermined number of measurement results are stored together with date and measurement time information obtained from a timer unit (not shown) for each individual number of the subject. When the predetermined number is exceeded, the latest measurement result is stored, for example, the old memory value is overwritten. In step S56, only the body composition value may be stored. Moreover, it is good also as memorize | storing only predetermined information among the numerical values of the body composition calculated by step S54.

  Next, the microcomputer 10 displays the calculated body composition numerical value on the display unit 20 (step S58). Here, the whole body composition and other information is displayed. As the whole body composition, for example, body fat percentage, muscle percentage, visceral fat level, and the like are displayed. In addition, for example, the weight value determined in step S40, BMI (physique index), basal metabolism, and an index indicating how many years the calculated basal metabolism corresponds (hereinafter referred to as “age index”) are also displayed. Is done. These pieces of information are displayed in the first display area 20.1 of the display unit 20. In the second display area 20.2, all of the human body diagram (whole body) is lit.

  In addition, when the first display area 20.1 of the display unit 20 is small, these pieces of information may be displayed in order. For example, as shown in FIG. 14, first, the body weight and basal metabolism are displayed (see FIG. 14 (a)), and then each time the setting / display changeover switch 306 is operated, the muscle rate and the body fat rate are sequentially displayed. Display (see FIG. 14B), BMI and visceral fat level display (see FIG. 14C), and age index display (see FIG. 14D), and these are repeatedly displayed. Also good. In FIG. 14, it is assumed that the measurement result of the subject with personal number 1 is displayed.

  For example, in FIG. 14A, the weight of 52.3 kg and the basal metabolism 1182 kcal are displayed in the first display area 20.1. In FIG. 14B, the muscle ratio 28.8% and the body fat percentage 23.0% are displayed in the first display area 20.1. In FIG. 14C, BMI 20.4 and visceral fat level 3 are displayed in the first display area 20.1. In FIG. 14D, the age indicator 27 is displayed in the first display area 20.1. Further, in FIGS. 14A to 14D, the entire human body diagram (whole body) is turned on in the second display area 20.2.

  When the process of step S58 ends, the process proceeds to step S60, and the microcomputer 10 determines whether or not the memory switch 307 has been pressed. When it is determined that the memory switch 307 has not been pressed (NO in step S60), it is subsequently determined whether or not the site-specific switches 302 to 305 have been pressed (step S64).

  If it is determined in step S64 that the region-specific switches 302 to 305 have not been pressed (NO in step S64), the microcomputer 10 turns off the body composition meter 100 and ends this measurement process (step S68).

  On the other hand, if it is determined in step S64 that any one of the region-specific switches 302 to 305 has been pressed (YES in step S64), the microcomputer 10 determines the body composition of the measurement site corresponding to the type of switch pressed in step S64. Is displayed on the display unit 20 (step S66). In this case, the body composition of the designated site to be measured is displayed in the first display area 20.1 of the display unit 20. In the second display area 20.2, the designated measurement site is lit up.

  Here, FIG. 15 shows a display example when one of the trunk switch 303, the leg switch 304, and the arm switch 305 is pressed among the body-specific switches 302 to 305 in step S64.

  FIG. 15A is a display example of the body composition of the trunk when the trunk switch 303 is pressed. For example, a muscle percentage of 32.1% and a body fat percentage of 25.3% are displayed. In the second display area 20.2, the trunk portion of the human body diagram is lit.

  FIG. 15B is a display example of the body composition of the leg when the leg switch 304 is pressed. For example, a muscle percentage of 50.0% and a body fat percentage of 33.8% are displayed. Also. In the second display area 20.2, the leg portion of the human body diagram is lit.

  FIG. 15C is a display example of the body composition of the arm when the arm switch 305 is pressed. For example, a muscle percentage of 45.0% and a body fat percentage of 36.4% are displayed. In the second display area 20.2, the arm portion of the human body diagram is lit.

  When the whole body switch 302 is pressed, the display returns to that shown in FIG.

  When the process of step S66 ends, the process returns to step S60 again.

  If it is determined in step S60 that the memory switch 307 has been pressed (YES in step S60), the microcomputer 10 displays the memory value that is the past measurement result stored in the external memory 33 as the first display on the display unit 20. The information is displayed in the area 20.1 (step S62).

  In this case, the memory value corresponding to the measurement site displayed immediately before is read out and displayed. For example, when the body composition of the leg is displayed immediately before, when the memory switch 307 is pressed, the past measurement result of the body composition of the leg is read and displayed.

  Further, in step S60, each time the memory switch 307 is pressed, the past measurement results of the corresponding measurement site are displayed retroactively, for example, one week ago and two weeks ago. Thereby, the change of the body composition compared with the past measured value can be grasped.

  When the process of step S62 ends, the process returns to step S60 again.

  Here, although the impedance value determined in step S52 is the impedance value of the whole body and three body parts (arm part, trunk part, leg part), the impedance value determined in step S52 is the whole body and The impedance values of five body parts (left arm, right arm, left leg, right leg, trunk) may be used. In this case, the body composition for the whole body and every five body parts may be calculated, and the calculated body composition numerical value may be stored and displayed for the whole body and every five body parts.

  As described above, according to body composition meter 100 in the embodiment of the present invention, it is possible to correct the daily fluctuation of the impedance for each part due to the influence of the movement of body moisture. Therefore, it is possible to accurately measure the body composition of the whole body and each part.

  Moreover, the impedance measurement method and the site | part impedance correction method which the body composition meter of this invention performs can also be provided as a program. Such a program can be recorded on an optical medium such as a CD-ROM (Compact Disc-ROM) or a computer-readable recording medium such as a memory card and provided as a program product. A program can also be provided by downloading via a network.

  The provided program product is installed in a program storage unit such as a hard disk and executed. The program product includes the program itself and a recording medium on which the program is recorded.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is an external appearance perspective view of the body composition meter in embodiment of this invention. It is a figure which shows the measurement attitude | position at the time of a test subject measuring a body composition using the body composition meter in embodiment of this invention. It is a block diagram of the body composition meter in the embodiment of the present invention. It is a front view of the 2nd housing | casing 2 of a body composition meter. It is a schematic diagram which shows the impedance component of each body part. It is a schematic diagram which shows the impedance component of the whole body. It is a figure for demonstrating the measuring method of the impedance of a left arm. It is a figure for demonstrating the measuring method of the impedance of a whole body. It is a figure for demonstrating the daily fluctuation | variation of the impedance according to site | part. It is a 1st flowchart which shows the flow of the measurement process of the body composition meter in embodiment of this invention. It is a 2nd flowchart which shows the flow of the measurement process of the body composition meter in embodiment of this invention. It is a flowchart which shows the flow of the impedance measurement process in embodiment of this invention. It is a flowchart which shows the flow of the site | part impedance correction process in embodiment of this invention. It is a figure which shows the example of a display of the measurement result of a whole body. It is a figure which shows the example of a display of the measurement result according to site | part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 1st housing | casing, 1.1, 1.2 mounting part, 2nd housing | casing, 2.1 Main body part, 2.2, 2.3 Grip part, 3 Cable, 4 Storage part, 10 Microcomputer 11 to 18 electrodes, 20 display section, 20.1 first display area, 20.2 second display area, 30 operation section, 31 power supply section, 32 weight measurement section, 33 external memory, 41A constant current generation circuit , 42 current application electrode switching circuit, 43 voltage measurement electrode switching circuit, 44 input switching circuit, 45 A / D conversion circuit, 100 body composition meter, 101 impedance measurement unit, 102 site-specific impedance correction unit, 103 body composition calculation , 133 Internal memory, 301 Power switch, 302 Whole body switch, 303 Trunk switch, 304 Leg switch, 305 Arm switch, 306 Setting / display switch, 307 Mori switch, 308 up and down switch, 309 personal number switch, 310 guest switch.

Claims (10)

First measuring means for measuring bioelectric impedance of the whole body for each of a plurality of different frequencies;
A second measuring means for measuring a bioelectrical impedance of at least one body part of the left arm, right arm, left leg, right leg, and trunk for each of the plurality of different frequencies;
First calculating means for calculating a plurality of first components constituting the whole body bioelectric impedance from the plurality of whole body bioelectric impedances measured by the first measuring means;
Second calculating means for calculating a plurality of second components constituting the bioelectric impedance of the body part from the bioelectric impedances of the body part measured by the second measuring means;
Correction means for correcting the remaining component of the plurality of second components by using the plurality of first components and at least one component of the plurality of second components. And a body composition meter.   The body composition meter according to claim 1, wherein the second measuring means measures bioelectrical impedances of a plurality of different body parts.   The component included in the plurality of first components and the component included in the plurality of second components are each at least one of an extracellular fluid resistance component and an intracellular fluid resistance component. The body composition analyzer according to claim 1, wherein the composition is a component corresponding to. Impedance calculation means for calculating bioelectrical impedance for body composition calculation of the body part from at least a plurality of components including the corrected component corrected by the correction means;
The body composition according to any one of claims 1 to 3, further comprising body composition calculation means for calculating a body composition of the body part from the bioelectric impedance for calculating the body composition calculated by the impedance calculation means. Total.   The body composition meter according to claim 4, wherein the body composition of the body part includes at least one of body fat mass, body fat percentage, lean mass, lean mass, bone mass, muscle mass, and muscle percentage.   The body composition calculating means calculates the body composition of the body part from the bioelectrical impedance for calculating the body composition calculated by the impedance calculating means and body specifying information such as age, sex, height and weight. The body composition meter according to claim 4.   The body composition meter according to claim 6, further comprising weight measuring means for measuring a weight included in the body specifying information.   The body composition meter according to claim 4, further comprising display means for displaying the body composition of the body part calculated by the body composition calculation means in association with the body part. A plurality of electrodes for contacting a plurality of parts of the body;
A switching means for switching the plurality of electrodes to select a pair of current electrodes for flowing an alternating current and a pair of voltage electrodes for measuring a voltage, respectively. 1. The body composition meter according to 1. The correcting means is
The ratio of the component corresponding to the resistance component of the extracellular fluid to the component corresponding to the resistance component of the intracellular fluid included in the plurality of first components, which is the first ratio, and the second ratio It is determined whether or not the ratio of the component corresponding to the resistance component of the extracellular fluid to the component corresponding to the resistance component of the intracellular fluid included in the plurality of second components matches. Including judgment means for
When the determining means determines that the first ratio and the second ratio do not match, the plurality of second ratios are set such that the first ratio and the second ratio match. The body composition meter according to claim 3, wherein a component corresponding to a resistance component of the extracellular fluid contained in the component 2 is corrected.

Images