Apparatus and method for measuring body composition

• US 6,280,396 B1
• Filed: 05/28/1999
• Issued: 08/28/2001
• Est. Priority Date: 08/03/1998
• Status: Expired due to Fees

• Current Assignee: American Weights and Measures
• Original Assignee: American Weights and Measures
• Inventors: Clark, Kenyon E.
• Primary Examiner(s): MANUEL, GEORGE C
• Application Number:
  US09/322,001
• Time in Patent Office: 823 Days
• Field of Search: 600/547, 600/506, 600/507, 600/587, 734/33, 702/50
• US Class Current: 600/547
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/4872 Body fat
• CPC Class Codes: A61B 5/6887 mounted on external non-worn devices, e.g. non-medical devices

Abstract

A body composition analyzer comprises a pair of handgrips extending laterally from either side of a housing containing other components of the device. Each handgrip comprises two electrodes positioned to make contact with a subject'"'"'s hands when grasped. A source of low voltage, high frequency alternating current is connected across first electrodes on each handgrip, so as to form a circuit passing through the subject'"'"'s body, and an impedance measuring instrument is connected to the second electrodes on each handgrip, to measure the impedance of the body in the circuit. The instrument also comprises a keypad for receiving data entered manually by the subject defining physical characteristics such as age, gender, height, weight, and the general physical condition of the subject. The input data is used to select one of a set of coefficients developed by regression analysis for use in an equation relating total body water to the impedance value and to the subject'"'"'s total body water content.

Claims

1. A body composition analyzer for determining the total body water content of a subject, comprising:

a mounting structure;

first and second pairs of electrodes, said pairs of electrodes being mounted on opposite lateral sides of said mounting structure, and disposed for simultaneous gripping of both pairs of electrodes by a subject;

means for supplying a high frequency alternating current signal across one of said first pair of electrodes and one of said second pair of electrodes, so that said signal passes through the body of the subject;

means for measuring the impedance of the body of the subject across the second of said first pair of electrodes and the second of said second pair of electrodes, and for providing an impedance signal responsive thereto; and

a controller for receiving input information including at least the height, weight, gender, and general physical condition of the subject, and for processing said impedance signal responsive to said input information to determine the total body water content of the subject;

wherein

said body composition analyzer is integrated with an electronic weighing scale and receives said input information concerning the weight of the subject directly from said scale.

2. The body composition analyzer according to claim 1, wherein said body composition analyzer is integrated with an electronic weighing scale such that when the subject stands on said scale, said electrodes extend in front of said subject for convenient gripping.

3. The body composition analyzer according to claim 1, wherein said controller processes said impedance signal to determine total body water content for a particular subject by selecting a set of coefficients from a group of sets of coefficients, each set of coefficients representing the result of a regression analysis performed on the body density-impedance relationship of a particular population segment, wherein the particular set of coefficients selected with respect to a particular subject are selected in response to said input information including at least the height, gender, and general physical condition of the subject.

4. The body composition analyzer according to claim 3, wherein said regression analysis is represented by an equation of the form:

5. The body composition analyzer according to claim 4, wherein the regression coefficients corresponding to the physical condition of the subject are selected responsive to identification of the subject as a member of one of four population segments identified as the obese, persons of normal physical condition, athletes, and body builders.

6. The body composition analyzer according to claim 4, wherein the regression coefficients corresponding to the age of the subject are selected responsive to determination that the subject'"'"'s age indicates membership in one of six age categories:

prepubescent, adolescent, young adult, adult, middle aged, and elderly.

7. The body composition analyzer according to claim 1, wherein said controller includes means for receiving input as to the height, gender, and general physical condition of the subject manually through a keypad.

8. The body composition analyzer according to claim 1, wherein said controller includes means for conversion of the calculated value for total body water content to a value for total body fat content.

9. A body composition analyzer for determining the total body water content of a subject, comprising:

a mounting structure;

first and second pairs of electrodes, said pairs of electrodes being mounted on opposite lateral sides of said mounting structure, and disposed for simultaneous gripping of both pairs of the electrodes by a subject;

means for supplying a high frequency alternating current signal across one of said first pair of electrodes and one of said second pair of electrodes, so that said signal passes through the body of the subject;

means for measuring the impedance of the body of the subject across the second of said first pair of electrodes and the second of said second pair of electrodes, and for providing an impedance signal responsive thereto; and

a controller for receiving input information including at least the height, weight, gender, and general physical condition of the subject, and for processing said impedance signal responsive to said input information to determine the total body water content of the subject; and

wherein said controller processes said impedance signal to determine total body water content for a particular subject by selecting a set of coefficients from a group of sets of coefficients, each set of coefficients representing the result of a regression analysis performed on the body density-impedance relationship of a particular population segment, and the particular set of coefficients selected with respect to a particular subject being selected in response to said input information including at least the height, gender, and physical condition of the subject.

10. The body composition analyzer according to claim 9, wherein the result of said regression analysis is represented by an equation of the form:

11. The body composition analyzer according to claim 9, wherein the regression coefficients corresponding to the physical condition of the subject are selected responsive to identification of the subject as a member of one of four population segments identified as the obese, persons of normal physical condition of the subject, athletes, and body builders.

12. The body composition analyzer according to claim 9, wherein the regression coefficients corresponding to the age of the subject are selected responsive to determination that the subject'"'"'s age indicates membership in one of six age categories:

prepubescent, adolescent, young adult, adult, middle age, and elderly.

13. The body composition analyzer according to claim 9, wherein said controller includes means for receiving input as to the height, gender, and physical condition of the subject manually through a keypad.

14. In combination, the body composition analyzer according to claim 9, and a weighing scale.

15. The combination of claim 14, wherein said scale is an electronic weighing scale, and wherein said controller is connected to said scale so as to receive said input information concerning the weight of the subject directly from said scale.

16. The combination of claim 14, wherein said weighing means is a balance beam weighing scale.

17. The combination of claim 16, wherein said pairs of electrodes are provided as exposed portions of opposed handgrips extending laterally outwardly from said mounting structure having been affixed to a central upright member of said balance beam weighing scale, for convenient gripping by a subject.

18. In combination, the body composition analyzer according to claim 9, and an exercise apparatus, wherein said body composition analyzer is mounted by said mounting structure to said exercise apparatus such that a subject may conveniently grasp said pairs of electrodes while performing exercises according to the normal function of the exercise apparatus.

19. The combination of claim 18, wherein said exercise apparatus is selected from the group including:

treadmills, stair-step machines, exercise bicycles, elliptical weight-training systems, and cross-training equipment.

20. The body composition analyzer according to claim 9, wherein said controller includes means for conversion of the calculated value for total body water content to a value for total body fat content.

21. In combination, an exercise apparatus whereby a subject may perform a specific biomechanical exercise, and a body composition analyzer for determining the total body water content of a subject, said body composition analyzer comprising:

a mounting structure;

first and second pairs of electrodes, said pairs of electrodes being mounted on opposite lateral sides of said mounting structure, and being disposed for simultaneous gripping of both pairs of the electrodes by a subject;

means for supplying a high frequency alternating current signal across one of said first pair of electrodes and one of said second pair of electrodes, so that said signal passes through the body of the subject;

means for measuring the impedance of the body of the subject across the second of said first pair of electrodes and the second of said second pair of electrodes, and for providing an impedance signal responsive thereto; and

a controller for receiving input information including at least the height, weight, gender, and general physical condition of the subject, and for processing said impedance signal responsive to said input information to determine the total body water content of the subject; and

wherein said controller processes said impedance signal to determine body fat content for a particular subject by selecting a set of coefficients from a group of sets of coefficients, each set of coefficients representing the result of a regression analysis performed on the body density-impedance relationship of a particular population segment, and the particular set of coefficients selected with respect to a particular subject being selected in response to said input information including at least the height, gender, and general physical condition of the subject; and

wherein

said body composition analyzer is mounted by said mounting structure to said exercise apparatus such that a subject may conveniently grasp said pairs of electrodes while performing exercises according to the function of the exercise apparatus.

22. The combination of claim 21, wherein said exercise apparatus is selected from the group including:

treadmills, stairstep machines, exercise bicycles, elliptical weight-training systems, and cross-training equipment.

23. The combination of claim 21, wherein said controller includes means for conversion of the calculated value for total body water content to a value for total body fat content.

24. The combination of claim 21, wherein the result of said regression analysis is represented by an equation of the form:

25. The combination of claim 21, wherein the regression coefficients corresponding to the physical condition of the subject are selected responsive to identification of the subject as a member of one of four population segments identified as the obese, persons of normal general physical condition, athletes, and body builders.

26. The combination of claim 21, wherein the regression coefficients corresponding to the age of the subject are selected responsive to determination that the subject'"'"'s age indicates membership in one of six age categories:

prepubescent, adolescent, young adult, adult, middle age, and elderly.

27. The combination of claim 21, wherein said controller includes means for receiving input as to at least the age, height, gender, and physical condition of the subject manually through a keypad.

28. A body composition analyzer for measuring the total body water content of a subject, said body composition analyzer comprising:

a housing for containing components of said body composition analyzer;

first and second pairs of electrodes, said pairs of electrodes being mounted on opposite lateral sides of said housing, and being disposed for simultaneous gripping of both pairs of the electrodes by a subject;

means for supplying a high frequency alternating current signal across one of said first pair of electrodes and one of said second pair of electrodes, so that said signal passes through the body of the subject;

means for measuring the impedance of the body of the subject across the second of said first pair of electrodes and the second of said second pair of electrodes, and for providing an impedance signal responsive thereto; and

a controller for receiving input information including at least the height, weight, gender, and general physical condition of the subject, and for processing said impedance signal responsive to said input information to determine the total body water content of the subject; and

wherein said controller processes said impedance signal to determine total body water content for a particular subject by selecting a set of coefficients from a group of sets of coefficients, each set of coefficients representing the result of a regression analysis performed on the body density-impedance relationship of a particular population segment, and the particular set of coefficients selected with respect to a particular subject being selected in response to said input information including at least the height, gender, and physical condition of the subject, and wherein the regression coefficients corresponding to the physical condition of the subject are selected responsive to identification of the subject as a member of one of four population segments identified as the obese, persons of normal general physical condition of the subject, athletes, and body builders.

29. The body composition analyzer of claim 28, wherein the result of said regression analysis is represented by an equation of the form:

30. The body composition analyzer of claim 29, wherein the regression coefficients corresponding to the age of the subject are selected responsive to determination that the subject'"'"'s age indicates membership in one of six age categories:

prepubescent, adolescent, young adult, adult, middle age, and elderly.

31. The body composition analyzer of claim 28, wherein said controller includes means for receiving input as to the age, height, gender, and general physical condition of the subject manually through a keypad.

32. The body composition analyzer of claim 28, wherein said controller further includes means for conversion of the calculated value for total body water content to a value for total body fat content.

33. The body composition analyzer of claim 28, wherein said controller further includes means for maintaining a count of the number of analyses performed relative to a fixed number of analyses having been authorized, and means for adding additional authorized analyses upon payment therefor.

34. A method for estimating total body water content of the body of a subject, comprising the steps of:

1) providing a controller for;

a) accepting input data for categorizing the subject according to the parameters of gender, age, and general physical condition;

b) accepting input data descriptive of the subject'"'"'s height and weight;

2) transmitting a high frequency alternating current signal into the body of the subject at first spaced contact points;

3) measuring the impedance of the body of the subject responsive to said current signal between second spaced contact points on the body of the subject; and

4) employing said controller to calculate the total body water content of the subject according to the equation;

35. The method of claim 34, wherein said first and second spaced contact points are located on the right and left hands of the subject.

36. The method of claim 35, wherein said controller is physically integrated and in signal communication relation with an electronic weighing scale, and wherein said step of accepting input data descriptive of the subject'"'"'s weight is performed by direct communication of said data from said scale to said controller.

37. The method of claim 34, wherein said steps of accepting input data for categorizing the subject according to the parameters of gender, age, and physical condition, and accepting input data descriptive of the subject'"'"'s height, are implemented using a keypad comprised by said controller.

38. The method of claim 34, comprising the further step of converting said calculated value for the total body water content of said subject to a value for the total fat content of the body of said subject.