Human Subject Index Estimation Apparatus and Method

• US 20080146961A1
• Filed: 10/29/2007
• Published: 06/19/2008
• Est. Priority Date: 12/13/2006
• Status: Active Grant

• Current Assignee: Tanita Corporation (Tanita)
• Original Assignee: Tanita Corporation (Tanita)
• Inventors: OKURA, Masashi, KASAHARA, Yasuhiro
• Granted Patent: US 7,962,205 B2
• Time in Patent Office: Days
• US Class Current: 600/547
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/107 Measuring physical dimensions, e.g. size of the entire body or parts thereof
• CPC Class Codes: A61B 5/1077 Measuring of profiles
• CPC Class Codes: A61B 5/4872 Body fat

Abstract

A CPU (170) of a human subject index estimation apparatus (1) computes a waist circumference based on body weight measured by a weight scale (110) and bioelectric impedance measured by a bioelectric impedance measurement unit (200A), and information such as age and height which was input through input unit (150). The computed waist circumference is stored, along with the information such as age and height, in a third storage unit (140) that is a rewritable non-volatile memory. The CPU (170) displays the waist circumference on display unit (160).

Claims

1. A human subject index estimation apparatus that estimates a circumference of a human subject at a predetermined position between the levels of the waist and the hips, comprising:

a weight scale that measures a weight of the human subject; and

a computer that executes a computation in accordance with an equation (A) thereby estimating the circumference, wherein the equation (A) is;

Y=a1*W+f(k)  

 

(A)

wherein;

Y is the circumference,

W is the weight,

a1 is a constant,

k is a variable, and

f(k) is a function of plural variables, the variables including the weight and at least one of sex, race, age, height, body mass index, bioelectric impedance, body fat percentage, and body fat mass.

2. A human subject index estimation apparatus according to claim 1,

wherein the computer changes the constant a1 and a constant contained in the function f(k) depending on at least one of sex and race of the human subject.

3. A human subject index estimation apparatus according to claim 1,

wherein the predetermined position is at the level of the waist,

wherein the computer executes the computation of the equation (A) using, as the function f(k), a function f(Z,H,E) as shown in an equation (B) which is:

f(Z,H,E)=a2*Z/H+a3*E  

 

(B)

wherein;

Z is bioelectric impedance,

H is height,

E is age, and

a2 and a3 are constants.

4. A human subject index estimation apparatus according to claim 1,

wherein the predetermined position is at the level of the hips,

wherein the computer executes the computation of the equation (A) using, as the function f(k), a function f(% Fat,BMI) as shown in an equation (C) which is:

f(% Fat,BMI)=a4* % Fat*BMI  

 

(C)

wherein;

% Fat is body fat percentage,

BMI is body mass index, and

a4 is a constant.

5. A human subject index estimation apparatus according to claim 1, further comprising a bioelectric impedance measurement device that measures bioelectric impedance between the left foot and the right foot,

wherein the computer executes the computation of the equation (A) using the measured bioelectric impedance.

6. A human subject index estimation apparatus according to claim 1,

further comprising a bioelectric impedance measurement device that comprises:

first to fourth electrodes contacting a left foot, a right foot, a left hand, and a right hand, respectively;

fifth to eighth electrodes contacting a left foot, a right foot, a left hand, and a right hand, respectively;

an electric current supplier that supplies an electric current between two of the first to fourth electrodes; and

a potential difference detector that detects a potential difference between two of the fifth to eighth electrodes;

wherein the bioelectric impedance measurement device switches the two electrodes to which the electric current is supplied and the two electrodes between which a potential difference is detected, to measure the bioelectric impedance of plural portions of the human subject, and the bioelectric impedance measurement device computes a bioelectric impedance of a trunk of the human subject based on the measured bioelectric impedance of the plural portions; and

wherein the computer executes the computation of the equation (A) using the measured bioelectric impedance.

7. A human subject index estimation apparatus according to claim 1, further comprising a storage device that stores the circumference actually measured at the predetermined location as an initial circumference value and stores the variable measured in a measurement of a first time as an initial variable value,

wherein the computer, in a measurement at a second time and subsequent times, i) computes a variable difference value that is a difference between the variable measured at this time and the initial variable value read from the storage device, ii) executes the computation of the equation (A) using the variable difference value instead of using the variable, thereby to compute one of an increased value and a decreased value of the circumference, and iii) computes the circumference as estimated at this time by adding the increased or decreased value of the circumference to the initial circumference value read from the storage unit.

8. A human subject index estimating method for estimating a circumference of a human subject at a predetermined position between the levels of the waist and the hips, comprising:

measuring a body weight of the human subject; and

executing a computation in accordance with an equation (A) thereby estimating the circumference, wherein the equation (A) is;

Y=a1*W+f(k)  

 

(A)

wherein;

Y is the circumference,

W is the weight,

a1 is a constant,

k is a variable, and

f(k) is a function of plural variables, the variables including the weight and at least one of sex, race, age, height, body mass index, bioelectric impedance, body fat percentage, and body fat mass.