Body composition measurement method and apparatus
First Claim
1. A body composition measurement method, in which an impedance of a body of a subject is measured and information about a body composition and/or health condition of the subject is estimated based on a measurement value of an impedance, or based on the measurement value of the impedance and body specific information, wherein:
- an entire human body is represented by a model in which the human body is divided into plural body parts, where the impedance of each body part can be approximately represented by a model composed of impedances respectively corresponding to at least fatty tissue, muscular tissue and osseous tissue connected in parallel, and component ratios of the tissues and electrical characteristics of the whole component tissues and each tissue can be regarded as fixed, an alternating current is supplied between two current-carrying electrodes attached to a surface of the body at positions located outer than both ends of a target body part selected from the plural body parts so that the alternating current flows through at least the target body part, a potential difference generated by the alternating current between both ends of the target body part is measured with two measuring electrodes attached to the surface of the body in the vicinity of the aforementioned ends or at positions lying not on a path of the alternating current but on paths each extending from the aforementioned ends, and the impedance corresponding to the target body part is derived from a measurement value of the potential difference and a current value, and information relating to the body composition and/or health condition of the target body part or the entire body of the subject is estimated from the value of the impedance, or from the value and the body specific information.
1 Assignment
0 Petitions
Accused Products
Abstract
To accurately measure the muscle mass, body-fat ratio and/or other information of the subject, the human body is divided into nine segments including the trunk, right and left forearms, right and left upper arms, right and left thigh, and right and left crura. Four distal voltage-measuring points Pv are determined at the wrists and ankles, and four proximal voltage-measuring points Pv are determined at the elbows and knees. Four current-carrying electrodes and four measuring electrodes are used. First, the measuring electrodes are attached to distal points, and the impedances of four limbs and the trunk are measured. Then, the measuring electrodes are moved to proximal points, and the impedances of four limbs and the trunk are measured. From the measurement result, the measurement value is calculated for each segment. Then, using estimation formulae created by a regression analysis based on the data collected with an MRI, the body composition such as a muscle mass is estimated from the measurement values of the impedances and body specific information including the height, weight, etc.
90 Citations
71 Claims
-
1. A body composition measurement method, in which an impedance of a body of a subject is measured and information about a body composition and/or health condition of the subject is estimated based on a measurement value of an impedance, or based on the measurement value of the impedance and body specific information, wherein:
-
an entire human body is represented by a model in which the human body is divided into plural body parts, where the impedance of each body part can be approximately represented by a model composed of impedances respectively corresponding to at least fatty tissue, muscular tissue and osseous tissue connected in parallel, and component ratios of the tissues and electrical characteristics of the whole component tissues and each tissue can be regarded as fixed, an alternating current is supplied between two current-carrying electrodes attached to a surface of the body at positions located outer than both ends of a target body part selected from the plural body parts so that the alternating current flows through at least the target body part, a potential difference generated by the alternating current between both ends of the target body part is measured with two measuring electrodes attached to the surface of the body in the vicinity of the aforementioned ends or at positions lying not on a path of the alternating current but on paths each extending from the aforementioned ends, and the impedance corresponding to the target body part is derived from a measurement value of the potential difference and a current value, and information relating to the body composition and/or health condition of the target body part or the entire body of the subject is estimated from the value of the impedance, or from the value and the body specific information. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A body composition measurement apparatus, including a measuring means for measuring an impedance of a body of a subject, and an estimating means for estimating information relating to a body composition and/or health condition of the subject based on a measurement value of the impedance or based on the measurement value and body specific information, wherein:
-
an entire human body is represented by a model in which the human body is divided into plural body parts, where the impedance of each body part can be approximately represented by a model composed of impedances respectively corresponding to at least fatty tissue, muscular tissue and osseous tissue connected in parallel, and component ratios of the tissues and electrical characteristics of the whole component tissues and each tissue can be regarded as fixed, and the measuring means include;
a) a current-generating means for generating an alternating current at a preset frequency;
b) at least two current-carrying electrodes to be attached to a surface of the body at positions outer than both ends of a target body part selected from the plural body parts to supply the alternating current through at least the target body part;
c) a voltage-measuring means, including at least two measuring electrodes to be attached to the surface of the body in the vicinity of the aforementioned ends of the target body part or at positions lying not on a path of the alternating current but on paths each extending from the aforementioned ends, for measuring a potential difference generated between the aforementioned ends of the target body part by the alternating current supplied from the current-carrying electrodes; and
d) a calculating means for calculating the impedance corresponding to the target body part from a measurement value of the potential difference and a current value of the alternating current, and the estimating means estimates the information relating to the body composition and/or health condition of the target body part or the entire body of the subject based on a value of the impedance calculated by the calculating means, or based on the value and the body specific information. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 40, 41, 42, 43, 44, 45)
-
- 38. The body composition measurement apparatus according to claim 38, which estimates the basal metabolic rate or energy metabolism mainly based on a muscle mass of a leg, or of a thigh and a crus.
-
46. A body composition measurement apparatus, comprising:
-
a) a measuring means for measuring an impedance of almost an entire body or a part of the body of a subject; and
b) an estimating means for estimating an ADL index for measuring an ability for activities of daily living of the subject based on a measurement value of the impedance, or based on the measurement value and body specific information. - View Dependent Claims (47, 49, 50, 51)
-
-
48. The body composition measurement apparatus according to claim 48, wherein the estimating means estimates a muscle mass of a predetermined part of the body that is essential for the activities of daily living, based on the measurement value of the impedance, or based on the measurement value and the body specific information, and further estimates, from the muscle mass, the force that the muscle concerned can exhibit.
-
52. A body composition measurement apparatus, comprising:
-
a) plural current-carrying electrodes and plural measuring electrodes to be attached to a body of a subject, to measure an impedance of a target part composed of one body part or two or more body parts connected in series, based on a model in which an entire human body is separated into plural body parts, where the impedance of each body part can be represented by a model composed of impedances respectively corresponding to at least fatty tissue, muscular tissue and osseous tissue connected in parallel, and component ratios of the tissues and electrical characteristics of the whole component tissues and each tissue can be regarded as fixed;
b) a current-supplying means for supplying an alternating current at a preset frequency via the current-carrying electrodes through at least the target part;
c) a voltage-measuring means for measuring a voltage generated by the alternating current between both ends of the target part; and
d) a calculating means for calculating the impedance corresponding to the target part from the voltage measured and a current value of the alternating current, and for estimating information relating to a body composition or health condition of the target part or entire body of the subject from a value of the impedance, or from the value and body specific information, using an estimation formula created based on a result of a measurement of the impedance for the entire body and/or each body part of each of plural pretest subjects, and based on body composition criteria information of the entire body and/or each body part of each of the pretest subjects measured and collected with an apparatus capable of acquiring cross-sectional images, or created by further adding body specific information of the pretest subjects. - View Dependent Claims (53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71)
-
Specification