U.S. patent application number 09/910309 was filed with the patent office on 2002-02-21 for body attribute analyzer with trend display.
Invention is credited to Alting-Mees, Adrian P., Drinan, Darrel, Levatter, Jeffrey I., Merz, Diethard.
Application Number | 20020022773 09/910309 |
Document ID | / |
Family ID | 22167030 |
Filed Date | 2002-02-21 |
United States Patent
Application |
20020022773 |
Kind Code |
A1 |
Drinan, Darrel ; et
al. |
February 21, 2002 |
Body attribute analyzer with trend display
Abstract
A body attribute analysis and display system provides a display
of averaged data for selected body attributes, such as body weight,
body fat percentage, and blood pressure, at a plurality of selected
intervals over a period of time. The user's body fat percentage is
determined by measuring the user's body impedance.
Inventors: |
Drinan, Darrel; (San Diego,
CA) ; Levatter, Jeffrey I.; (Rancho Santa Fe, CA)
; Merz, Diethard; (Darmstadt, DE) ; Alting-Mees,
Adrian P.; (Vista, CA) |
Correspondence
Address: |
Hopgood, Calimafde,
Judlowe & Mondolino
Suite 4100
60 East 42nd Street
New York
NY
10165
US
|
Family ID: |
22167030 |
Appl. No.: |
09/910309 |
Filed: |
July 20, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09910309 |
Jul 20, 2001 |
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09291546 |
Apr 14, 1999 |
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60081886 |
Apr 15, 1998 |
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Current U.S.
Class: |
600/300 |
Current CPC
Class: |
A61B 5/0537 20130101;
Y10S 128/903 20130101; A61B 5/7475 20130101; A61B 5/742 20130101;
A61B 5/4869 20130101; A61B 5/6887 20130101; A61B 2560/0468
20130101; A61B 5/103 20130101 |
Class at
Publication: |
600/300 |
International
Class: |
A61B 005/00 |
Claims
What is claimed is:
1. A system for measuring and displaying body attribute information
comprising: a measuring device for measuring a current value of at
least one body attribute; a storing device for storing the results
of measurements of said at least one body attribute taken over a
plurality of prior measuring intervals; a computing device for
computing an average value of said at least one body attribute
measured during one or more of said prior measuring intervals in an
event more than one such measurement of said at least one body
attribute is made during said one or more prior measuring intervals
and storing said average value as a prior measurement value; and a
display device operatively coupled to said storing device for
displaying the results of the current measurement along with data
representative of at least one prior measurement of said at least
one body attribute.
2. The system of claim 1, in which said display device comprises a
graphic display of the results of the current and at least one
prior measurement of at least two body attributes.
3. The system of claim 2, in which said body attributes include
body weight and body fat percentage.
4. The system of claim 3, further comprising a measuring unit for
measuring the user's body weight and bioimpedance, and a computing
unit for computing the user's body fat percentage from said
measured weight and bioimpedance.
5. The system of claim 1, further comprising an input unit for
inputting one of a plurality of user identification codes, each of
said codes being associated with one of a corresponding plurality
of potential users, said display device being operative to display
body attribute data only for the user identified by the inputted
personal identification code.
6. The system of claim 1, further comprising a comparing unit for
comparing a current body attribute measurement against a stored
value of body attribute measurement, and a preventing device for
preventing access to the stored body attribute data if the stored
body attribute data deviates from the current body attribute data
by a predetermined amount.
7. The system of claim 6, further comprising a storing unit for
storing body attribute measurement data only for data of a body
attribute measurement taken during a predetermined period of
time.
8. The system of claim 1, further comprising a base unit including
said measuring device and a display unit remote from said base
unit, said remote display unit including said display device, and a
transmitting device in said base unit for transmitting current and
prior body attribute data from said base unit to said remote
display unit.
9. The system of claim 1, in which said body attribute includes one
or more of body weight, body fat percentage, fat free mass, lean
body mass, body mass index, total water content and blood
pressure.
10. The system of claim 9, in which said display device comprises a
graphic display of the results of the current and at least one
prior measurement of at least two body attributes.
11. The system of claim 10, in which said body attributes include
body weight and body fat percentage.
12. The system of claim 11, further comprising a measuring unit for
measuring the user's body weight, and means for computing the
user's bioimpedance and at least one other body attribute from said
value of bioimpedance.
13. The system of claim 4, further comprising a base unit including
said measuring device, and a display unit remote from said base
unit and including said display device, and a transmitting unit in
said base unit for transmitting the current and prior body
attribute data from said base unit to said remote display unit.
14. The system of claim 13, in which said transmitting unit
includes an infrared transmitter, and said display unit includes an
infrared receiver.
15. The system of claim 4, comprising a base unit including said
measuring unit, and a display unit remote from said base unit and
including said display device, and a transmitting unit in said base
unit for transmitting the current and prior body attribute data
from said base unit to said remote display unit.
16. A body attribute display system comprising: a measuring and
computing device for measuring and computing at least first and
second different body attributes of a user; a storing device
coupled to said measuring and computing device for storing data
representative of at least one measurement of said first and second
body attributes made during at least one prior time interval; and a
display device coupled to said storing device for displaying said
at least one prior measured value of said first and second body
attributes, along with a display of current values of said first
and second body attributes.
17. The system of claim 16, in which said body attributes include
body weight and body fat percentage, said measuring device
effective for measuring the user's bioimpedance, and a signaling
device for deriving from said measuring device a signal
representative of the user's body weight.
18. The system of claim 16, further comprising an input device for
inputting one of a plurality of personal identification codes, said
display device being effective to display body attribute data only
for a user identified by an inputted personal identification
code.
19. The system of claim 16, further comprising a computing unit for
computing the average values of body weight and body fat percentage
taken during one or more of said prior intervals in the event more
than one of such measurements is made during that prior
interval.
20. The system of claim 16, further comprising an input device for
inputting one of a plurality of personal identification codes, each
of said codes being associated with one of a corresponding
plurality of users, said display device, in response to said input
code, displaying body attribute data only for a user identified by
an inputted personal identification code.
21. The system of claim 20, further comprising a computing unit for
computing the average values of body weight and body fat percentage
taken during one of said prior intervals in the event more than one
of such measurements is made during that interval.
22. The system of claim 21, further comprising electrodes adapted
to conduct a signal current transmitted through a user's body, for
measuring said user's bioimpedance.
23. The system of claim 21, in which said computing unit for
computing body fat percentage includes a measuring unit for
measuring the user's bioimpedance, said bioimpedance measuring unit
including a current source, a first pair of electrodes coupled to
said current source, a second pair of electrodes, and a voltage
drop measuring unit for measuring the voltage drop across said
second pair of electrodes.
24. The system of claim 16, in which said measuring unit and said
computing unit are included in a base sensor unit, and said display
device is included in a display unit remote from said base sensor
unit, said base sensor unit comprising a transmitting device
coupled to said computing unit for transmitting the computed body
attribute data to said remote display unit.
25. The system of claim 24, in which said transmitting device
includes an infrared transmitter, said display unit comprising an
infrared receiver.
26. The system of claim 23, in which said measuring unit and said
computing unit are included in a base sensor unit, and said display
device is included in a display unit remote from said base sensor
unit, said base sensor unit comprising a transmitting device
coupled to said computing unit for transmitting the computed body
attribute data to said remote display unit.
27. The system of claim 26, in which said transmitting device
includes an infrared transmitter, said display unit comprising an
infrared receiver.
28. A system for measuring and displaying current and previously
measured body attributes for a plurality of authorized users, said
system comprising: a security or identification device for
comparing current body factor measurements and prior stored body
attribute measurements; and a preventing device effective to
preclude a current user from gaining access to stored body
attribute data, when the current and stored body attribute data
deviate by more than a predetermined amount.
29. The system of claim 28, in which a display device comprises a
graphic display of the results of the current and at least one
prior measurement of at least two body attributes.
30. The system of claim 29, in which a measuring device and said
computing device are included in a base sensor unit, and said
display device is included in a display unit remote from said base
sensor unit, said base sensor unit comprising a transmitting device
coupled to said computing device for transmitting the computed body
attribute data to said remote display unit.
31. The system of claim 28, in which said security or
identification device includes a comparing unit for comparing the
current body attribute measurements with prior body attribute
measurements for a user identified by the identification code
entered by the current user.
32. The system of claim 28, further comprising a storing device for
storing body measurement data only for measurements taken during a
predetermined period of time.
33. A system for measuring and displaying body attributes for a
plurality of potential users comprising: a display device for
displaying the results of current and prior body attribute
measurements; an input device for inputting one of a plurality of
user identification codes, each of said codes being associated with
one of a corresponding plurality of potential users; and a
permitting device for permitting a display of stored body attribute
information only for the user identified by the inputted user
identification code.
34. The system of claim 33, further comprising a storing device for
storing body measurement data only for measurements taken during a
predetermining period of time.
35. The system of claim 33, further comprising: a comparing device
for comparing a current body attribute measurement a gainst a
stored value of an authorized user's body attribute measurement;
and a preventing device for preventing access to the stored
measurement data when the stored measurement data deviates from the
current measurement data by a predetermined amount.
36. The system of claim 34, further comprising: a comparing device
for comparing a current body attribute measurement against the
stored value of an authorized user's body attribute measurement;
and a preventing device for preventing access to the stored
measurement data when the stored measurement data deviates from the
current measurement data by a predetermined amount.
37. A system for measuring and displaying measured body attributes
comprising: a measuring device for measuring body attributes; a
storing device for storing the results of current and prior body
attribute measurements; and a storing unit for storing in said
storing device only the results of a body attribute measurement
taken during a predetermined period of time.
38. The system of claim 37, in which said body attribute includes
one or more of body weight, body percentage, fat free mass, lean
body mass, body mass index, total water content, and blood
pressure.
39. The system of claim 37, further comprising: a comparing device
for comparing a current body attribute measurement against the
stored value of an authorized user's body attribute measurement;
and a preventing device for preventing access to the stored
measurement data if the stored measurement data deviates from the
current measurement data by a predetermined amount.
40. The system of claim 37, further comprising a display device for
displaying a graphic display of the results of the current and at
least one prior measurement of at least two body attributes.
41. The system of claim 37, in which said body attributes include
body weight and body fat percentage.
42. The system of claim 37, further comprising a computing device
and a display device, wherein said measuring device and said
computing device are included in a base sensor unit; and said
display device is included in a display unit remote from said base
sensor unit, said base sensor unit comprising a transmitting device
coupled to said computing device for transmitting the computed body
attribute data to said remote display unit.
43. The system of claim 42, in which said transmitting device
includes an infrared transmitter and said display unit includes an
infrared receiver.
44. A system for measuring and displaying at least one body
attribute comprising: a base unit including a measuring device for
measuring said at least one body attribute; a storing device for
storing the result of the measurement of said body attribute; a
display unit remote from said base unit, said remote display unit
including a display device for displaying the results of a current
and at least one prior measurement of said body attribute; and a
transmitting device in said base unit for transmitting stored and
current body attribute information to said remote display unit.
45. The system of claim 44, in which said body attribute includes
one or more of body weight, body fat percentage, fat free mass,
lean body mass, body mass index, total water content, and blood
pressure.
46. The system of claim 44, in which said body attributes include
body weight and body fat percentage.
47. The system of claim 45, further comprising electrodes adapted
to conduct a signal current transmitted through a user's body, for
measuring said user's bioimpedance.
48. The system of claim 45, in which said measuring device includes
a measuring unit for measuring a user's bioimpedance, said
measuring unit including a current source, a first pair of
electrodes coupled to said current source, a second pair of
electrodes, and a voltage measuring device for measuring the
voltage drop across said second pair of electrodes.
49. The system of claim 44, in which said display device comprises
a graphic display of the results of the current and at least one
prior measurement of at least two body attributes.
50. The system of claim 49, in which said body attributes include
body weight and body fat percentage.
51. The system of claim 44, further comprising an input device for
inputting one of a plurality of user identification codes, each of
said codes being associated with one of a corresponding plurality
of potential users, said display device displaying body attribute
data only for the user identified by the inputted personal
identification code.
52. The system of claim 44, further comprising a comparing device
for comparing a current body attribute measurement against the
stored value of an authorized user's body attribute measurement,
and a preventing device for preventing access to the stored
measurement data if the stored measurement data deviates from the
current measurement data by a predetermined amount.
53. The system of claim 52, further comprising a storing unit for
storing body measurement data only for measurements taken during a
predetermined period of time.
54. The system of claim 44, in which said transmitting device
includes an infrared transmitter, said display unit comprising an
infrared receiver.
55. A system for measuring and displaying at least one body
attribute of an individual comprising: a measuring device for
measuring the individual's bioimpedance; and a modifying device for
modifying the measured bioimpedance by an amount based on the time
of day the measurement is made.
56. The system of claim 55, in which said body attribute is body
fat percentage.
57. The system of claim 55, in which said measuring device is
included in a base sensor unit, and further including a display
device for displaying the measured body attribute, said display
device being included in a display unit remote from said base
sensor unit.
58. The system of claim 57, in which said base sensor unit includes
a transmitting device operatively coupled to said measuring device
for transmitting data representative of the measured body attribute
to said display unit.
59. A system for measuring and displaying body attribute
information comprising: a measuring device for measuring the
current value of a body attribute which includes at least a user's
body fat percentage; a storing device for storing the results of a
measurement of said body attribute taken during at least one prior
interval; and a display device operatively coupled to said storing
device for displaying the results of the current measurement of the
user's body fat percentage along with data representative of said
at least one prior measurement of the user's body fat
percentage.
60. The system of claim 59, in which said display device comprises
a graphic display of the results of the current and said at least
one prior measurement of the user's body fat percentage and of at
least one additional body attribute.
61. The system of claim 60, in which said additional body attribute
includes body weight.
62. The system of claim 59, further comprising a measuring unit for
measuring the user's body weight and bioimpedance, and a computing
device for computing the user's body fat percentage from the
measured weight and bioimpedance.
63. The system of claim 59, further comprising an input device for
inputting one of a plurality of user identification codes, each of
said codes being associated with one of a corresponding plurality
of potential users, said display device being operative to display
body attribute data only for the user identified by the inputted
personal identification code.
64. The system of claim 59, further comprising: a comparing device
for comparing a current body attribute measurement against a stored
value of body attribute measurement; and a preventing device for
preventing access to the stored body attribute data when the stored
body attribute data deviates from the current body attribute data
by a predetermined amount.
65. The system of a claim 59, further comprising: a base unit
including said measuring device and a display unit remote from said
base unit, said remote display unit including said display device;
and a transmitting device in said base unit for transmitting
current and prior body attribute data from said base unit to said
remote display unit.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 09/291,546 filed on Apr. 14, 1999, which is
based on a provisional application Serial No. 60/081,886 filed on
Apr. 15, 1998, the contents of which are incorporated by reference
herein.
FIELD OF INVENTION
[0002] The present invention relates generally to the measurement
of body attributes, and more particularly to a bioelectrical body
analyzer that displays trend data of one or more body attributes,
such as weight, body fat, and blood pressure.
BACKGROUND
[0003] In recent years, there has been an increasing interest among
health-conscious individuals to monitor, on a continuing basis,
certain of their physical parameters, or attributes, such as body
weight, blood pressure and heart rate. There has also been an
increasing interest, particularly among dieters and individuals who
engage in exercise or athletic activities, to obtain an accurate
determination of the percentage of their weight that is made up of
body fat.
[0004] It has long been known that risk of developing certain
life-shortening illnesses, such as coronary artery disease,
hypertension, and diabetes, is related to obesity. It has recently
been determined that the health risks associated with obesity are
more related to increased body fat than to increased body weight
per se. Too little body fat also poses a health risk because the
body requires a certain amount of fat for certain normal
physiological functions such as cell membrane formation and thermal
insulation.
[0005] A number of methods are known to determine the body
composition in vivo. The most accurate of these are, however,
expensive and time-consuming methods such as dual x-ray
absorptiometry, dilution techniques and computer topography. These
methods, because of their expense and complexity, are not suitable
for use in the home or as a consumer device. Other less costly and
complex procedures for measuring body fat content are also
known.
[0006] One such technique, near infrared interaction, is based on
the observation that human body fat absorbs light in the
near-infrared spectrum. The percent of body fat is calculated from
the value of absorbed infrared light in combination with the
individual's height and weight. The main drawback of this technique
is that the measurement is made at only one location of the body;
its accuracy has also been questioned.
[0007] In another known technique to determine body fat content,
the thickness of skinfolds formed at defined body sites is
measured. The sum of these thicknesses correlates with body fat
content. Although this method is one of the most commonly used
methods to determine body fat, its use requires a considerable
level of skill and training in order to obtain reproducible
results. Moreover, since several sites of measurement are very
difficult to reach this technique is impractical for use by the
person who is trying to make a measurement of his or her body
fat.
[0008] The use of ultrasound to measure the thickness of the fat
layer of the skin, another known technique to measure body fat,
involves the reflection of ultrasound waves at the boundaries of
the skin layers; the delay of reflected pulses is proportional to
that layer of thickness. The major drawbacks in this technique are
the need to use fluid for introducing the ultrasound into the skin,
the variability of the thickness as a function of pressure and the
often observed inaccuracy due to artifacts and reflections at
components other than the skin boundaries.
[0009] It is known that body fat content as a percentage of total
body weight may be measured by measuring the body's electrical
impedance, such as between the individuals feet or between the foot
and arm. This technique is known as a bioelectric impedance
analysis (BIA). As disclosed in U.S. Pat. No. 5,415,176, body
impedance along with the individuals height and weight can be used
to calculate an estimate of the individual's body density and body
fat percentage by the use of a known algorithm that relates body
fat to body impedance.
[0010] The use of bioelectric impedance analysis to measure body
composition, and specifically body fat, is based on the different
conductive and dielectric properties of various biological tissues
at various frequencies of current. Tissues that contain a lot of
water and electrolytes are highly conductive, whereas fat, bone,
and air-filled spaces such as the lungs are highly resistive or
dielectric tissues. The volume of these tissues can thus be
determined from measurements of their combined resistances.
[0011] As shown in U.S. Pat. No. 5,415,176, in a typical BIA
measurement a pair of electrodes is applied to the individual's
extremities such as the hands or feet. Low-current (less than 1 mA)
source or generator is applied across a first pair of electrodes,
and the voltage across a second pair of electrodes is measured.
Since the value of current is known, the voltage drop provides an
accurate indication of the body's impedance. The body impedance,
determined in this manner, along with the individual's body weight
and height, can then, as noted, be used to calculate or estimate
the individual's body fat or body density.
[0012] Although the knowledge of an individual's body fat is of
considerable value, more useful information in this regard would be
an indication of body composition, such as body fat, over time,
such as over a period of weeks or months. Such historical
information is particularly valuable to individuals who are on a
diet or fitness program as an indication of the progress they have
made in reducing body fat or weight over a period of time. This
trend information allows the individual to better monitor and thus
control his or her progress in reducing body fat and body weight by
being able to observe the change over time of weight and/or body
fat percentage.
[0013] A system that provides such a so-called historical or trend
display of body weight over a specified period of time is
disclosed, for example, in U.S. Pat. Nos. 3,512,592 and 4,301,879.
As shown in the latter, weight data from prior measurements are
stored in memory and extracted, along with time data, to generate a
display that represents the individual's body weight as a function
of time.
[0014] The prior body weight trend display systems are, however,
complicated to use and provide only limited information with regard
to the displayed variations of body weight. Particularly, the known
systems are typically usable by only one individual and only
provide information on a single aspect of body composition namely
body weight. Moreover, the known body measurement and display
systems are often not accurate, and the measured data is often not
repeatable, because, for example, they fail to take into account
variations in body fluid content that occur during the day, and
they do not provide averaging of multiple body measurements.
SUMMARY OF THE INVENTION
[0015] The body composition analyzer of the present invention
provides a display of the user's current body composition
parameters such as body fat content or percentage and/or body
weight, as well as a display of the prior trend or historical data
of those parameters over a period of time. The analyzer base unit,
in one embodiment of the invention, includes a set of electrodes
connected to a current source to provide an electrical signal
representative of the user's bioelectrical impedance or
bioimpedance, which is used to compute the user's body fat
percentage. This information and the user's measured body weight
may be displayed on the base unit and/or transmitted to a remote
display unit.
[0016] In one embodiment of the invention herein disclosed, the
user places the front part of his or her foot on a pair of sensor
electrodes and heels on a pair of stimulus electrodes. The measured
voltage drop across the sense electrodes is proportional to the
impedance (resistance) between the sense and stimulus electrodes,
and is indicative of the user's body fat percentage. A load cell in
the base unit produces an additional signal that represent the
user's body weight. The body weight and body fat (impedance)
measurement sequence is controlled by a microprocessor that also
computes the user's body fat percentage in accordance with an
algorithm stored in its software as a function of the measured
bioimpedance along with other factors, such as the user's height
and weight.
[0017] The user's current body fat percentage and body weight data
are displayed as a numerical readout, along with graphical trend
data of those parameters based on a series of prior measurements of
body fat percentage and body weight taken at specified (e.g. weekly
or monthly) intervals. Each time a new measurement of body weight
and body fat percentage is made, the current data is displayed
along with the stored results of prior measurements of those
parameters to provide a trend or historical data for the user that
indicates how these body composition factors have changed over
time.
[0018] In a further aspect of the invention, the displayed trend
data (e.g. body weight and body fat percentage) are average values
of measurements taken during each display interval. Thus, if trend
data is displayed for each week, and the user has made two or more
measurements in any single week, the values of those measured body
weight and body fat percentage measurements are averaged, and the
computed average body weight and body fat percentage data are
stored in memory for later display.
[0019] In a further aspect of the invention, a number of different
authorized users may employ the body composition analyzer to
display their current and body composition trend data. To this end,
an authorized user, before making a new measurement, enters his or
her unique identification code so that only previously stored
measured body composition data for that user is taken from the
memory to create a trend display for that user. Information
concerning each authorized user's height, gender and the like is
also stored in memory to allow a computation of, e.g., body fat
percentage, to be made for that user.
[0020] In yet a further aspect of the invention, measurements of
body composition factors taken during certain times of the day
outside of a prescribed time interval or window (e.g. in the
morning), are displayed, but not stored for inclusion in trend
history with other body composition measurements taken during the
prescribed time interval. In this manner, the body composition
trend data that is displayed is more accurate since it reflects
measurements made during the same time of day over a period of
weeks or months, and, as a result, is not affected by the normal
variations of body fluid content and weight that occur in most
individuals during the course of a day.
[0021] In a further aspect of the present invention, use of and
access to the system by an unauthorized user is prevented by
comparing a current body composition measurement for a user who has
entered one of the available personal identification codes against
stored prior body composition data for the user to whom that
identification code has been assigned. If the current measurement
deviates from the stored data by a predetermined amount for a given
time period, e.g. 5 percent for a one-week interval, the user is
identified as being unauthorized and is prevented from gaining
access to any of the stored data.
[0022] The present invention relates to a body composition trend
data analyzer and display system, substantially as defined in the
appended claims and as described in the following detailed
specification as considered together with the accompanying
drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIGS. 1A and B are isometric views showing the use of the
body composition analyzer in accordance with two embodiments of the
invention;
[0024] FIG. 2 an elevation of a display unit that provides a
display of body fat percentage and body weight as used in the body
composition analyzer of the invention;
[0025] FIG. 3 is a schematic functional block diagram of the body
composition analyzer in accordance with a first embodiment of the
invention;
[0026] FIGS. 4A and 4B are schematic block diagrams of a body
composition analyzer in which the display unit is remote from the
base unit in accordance with a second embodiment of the
invention;
[0027] FIG. 5 is a schematic diagram of a bioimpedance processor
that may be used in the base unit of the body composition analyzers
of FIGS. 3 and 4A;
[0028] FIG. 6 is a schematic circuit diagram of the stimulus and
sense electrodes of the bioimpedance processor of FIG. 5;
[0029] FIGS. 7, 8, 9, and 10 are logic flow diagrams describing
different sequences of operation of the body composition analyzer
of the invention; and
[0030] FIG. 11 is a graphical depiction of the correction of
bioimpedance measurement as a function of the time the measurement
was made in accordance with a possible implementation of the
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] The body composition analyzer system of the invention, as in
the embodiments generally designated as 10a and 10b in FIG. 5, 1A
and 1B respectively, measures, computes and displays certain body
composition attributes, such as body fat percentage and body
weight. It will be understood that the system of the invention may
also be used to measure and display other body attributes such as
fat-free mass, lean body mass, body mass index, total body water,
blood pressure, and other parameters which affect the body's
bioimpedance. The body composition analyzer of the invention may be
incorporated in a unitary base assembly 10a, as in the embodiment
of FIG. 1A, and includes a graphic display unit 12a, which displays
the current measured and computed body composition information
along with a trend display of corresponding information obtained in
prior measurements taken during a selected number of prior time
intervals (e.g. a week). The measured body composition information,
both current and trend data, may also be displayed at a remote
display unit 12b, separate from the base unit 10b, as described in
greater detail below with reference to the embodiment of the
invention illustrated in FIGS. 4A and 4B.
[0032] The graphical body composition trend information is,
according to one aspect of the invention, produced of the average
computed values of specified body composition attributes that were
measured during a selected display interval. If desired, maximum or
minimum values of body composition attributes that are measured
during that interval, or any other value of a body composition
attribute that may be of interest, may also be computed and
displayed. Thus, if weekly trend information is displayed, and a
body composition measurement is made more than once during any
given week, the displayed information for that week (or maximum or
minimum) is computed as the average of the two or more measurements
made during that week.
[0033] As shown in FIG. 2, the graphic display unit 12, which, as
noted, may be formed integral with the sensor unit or separate and
remote therefrom, includes a viewing section 14 that has a
numerical value area 16 and a trend graph area 18, which
respectively provide an LED numerical display and graphical
displays. Area 16 provides a first numerical indication of the
user's body weight at 20, and a second numerical indication of
either the user's body fat percentage, fat free mass, or body mass
index in accordance with the user's choice made by operation of the
display button 24. The fat free mass is the inverse of the body fat
percentage, and the body mass index is the ratio of the square of
the user's height to his or her weight.
[0034] The trend graph area 18 includes a first bar graph display
26 that includes a plurality (here eight) of vertical bars 30. The
height of each bar 30 is proportional to the average value of body
weight for each time interval (week) for an eight-week period, as
indicated by the numerals 1-8. Similarly, a second plurality of
bars 32 indicate the trend over a similar eight-week period, for
example, of the user's body fat percentage. For each series of bar
graphs 30, 32, bar 8 represents the current or last-taken body fat
or body weight measurement. To provide a clear visual display of
the trend data, the bars 30 indicating body weight and bar 32
indicating body fat percentage may be of contrasting colors, as
indicated in FIG. 2. The bars 30, 32 may also be of contrasting
shapes or patterns, or they may be positioned at different
locations of the trend graph display. The body weight and body fat
percentage trends are displayed upon the operation of the display
trend button 34.
[0035] The body composition analyzer of the invention may display
trend body composition data for a plurality, here four, different
authorized users. To this end, each authorized user is assigned a
code number, here shown as 1, 2, 3 or 4. At the beginning of each
measurement the user inputs his/her personal code input at the
corresponding numbered select button 36, so that the trend display
produced in display area 18 will be unique for that user. The use
of the analyzer by a guest user, as described in greater detail
below, is enabled by the operation of the guest (x) button 35. The
operation of the enter button 38 selects the currently displayed
option and the operation of the up/down arrows button 40 allows the
user to scroll through the options displayed in areas 16, 18.
[0036] The base unit of the body composition analyzer, which may
have the general overall appearance and size of a conventional
bathroom scale, includes, as in the embodiments of the invention
illustrated in FIGS. 1A and 1B, a pair of heel or sense electrodes
42, 44, and a pair of toe or stimulus electrodes 46, 48 on its
upper surface. The base unit also includes, as shown in FIGS. 5 and
6, a bioimpedance processor 52 that includes a constant current
generator 50 connected to stimulus electrodes 46, 48. Current
generator 50 supplies an imperceptibly low-level alternating
current at a typical frequency of 50 kHz to electrodes 42, 44. As
described in greater detail below, the bioimpedance processor 52
senses a voltage V.sub.B1o across the sense electrodes, 42, 44
which, along with the sensed current I.sub.B1o is used to compute
the user's bioimpedance Z.sub.B1o which, in turn, is used to
compute the user's body fat percentage.
[0037] The control or sensor unit 54 included in the base unit also
includes a temperature sensor 56 and a load cell processor 58 which
receive an analog voltage from an external load cell 60 that is
proportional to the user's body weight. Load cell 60 may include a
plurality of resistances that vary in accordance with the user's
weight and which are configured as a Wheatstone bridge to produce
an analog voltage that is proportional to the value of that
resistance.
[0038] The analog output voltage of the bioimpedance processor 52,
temperature sensor 56 and load cell processor 58, which
respectively indicate the user's bioimpedance, the ambient
temperature, and the user's weight, are applied to the inputs of an
analog multiplexer 62, which also receives a control signal from a
microprocessor 64. The ambient temperature is sensed and measured
in the microprocessor to make adjustments for thermal drifts. The
output of the multiplexer 62 is applied to the input of an
analog-to-digital converter (ADC) 66 which converts the selected
output analog signal of the multiplexer 62 to a corresponding
digital signal, which, in turn, is applied to an input of the
microprocessor 64.
[0039] The microprocessor 64 also receives the user's
identification and previously entered data regarding the user's
height, sex, and fitness level. Microprocessor 64 contains
appropriate software to perform specified control and computation
functions including the computation of the user's body fat
percentage from the input bioimpedance and the other input data in
accordance with an algorithm, such as the following:
X=a*ht.sup.2/Z+b*wt+c*age+d*sex+e*FL+f
[0040] where
[0041] a, b, c, d, e, and f are constants
[0042] ht =height
[0043] Z =body bioimpedance
[0044] wt =weight
[0045] sex =0/1 for male/female
[0046] FL =fitness level
[0047] X =body fat percentage
[0048] The weight and body fat percentage data computed in
microprocessor 64 is applied to an LCD display 68 to provide a
visible numerical display of that data, as illustrated in FIG. 2.
The output of microprocessor 64 may also, as shown, be applied to
an LED drive 70 the output of which is applied to LED indicators
72, which provide visual information to the user of system status,
e.g., when a measurement sequence has been completed, and the
detection of an error condition. Status information in audible form
may also be provided by a beeper 74 which receives status
information from the microprocessor 64. An output of microprocessor
64 may also be applied to a test and calibration interface 76,
which includes a set of electrical contacts that allows serial data
to be transferred between the microprocessor and a remote test and
calibration station (not shown).
[0049] A key matrix 80 included in the sensor unit 54 is employed
by the individual to enter data to the microprocessor 64 such as
his/her personal identification number, height, gender, age, and
physical profile, the latter being represented in an increasing
order of fitness by a number from 1 to 5. An output of the
microprocessor 64 is also connected to receive data from, and
transmit data to a data memory, here shown as an EEPROM 82.
[0050] Also included in the base control unit 54 is a power supply
84 which supplies a d.c. operating voltage to the multiplexer 62
and microprocessor 64. Power supply 84 receives its operating
voltage from an external battery pack 86. An external time base or
system clock generator 88 provides clock signals at a predetermined
frequency to the microprocessor 64 to control the computation and
general digital processing functions that are performed in the
microprocessor.
[0051] Referring again to FIG. 5, the bioimpedance processor
further includes a sine converter circuit 92 which receives a logic
control signal Vin from the microprocessor 64 and converts that
signal to a sinusoidal signal with a minimally low harmonic
content. The sinusoidal output voltage of circuit 92 is converted
in current source 50 to a programmed control current Ibio that is
applied, as described above, to the stimulus electrodes 46, 48. The
a.c. output of the sense electrodes 42, 44 is applied to a detector
that includes an amplifier 94 and a rectifier 96 that converts the
ac output of the sense electrodes to a voltage V.sub.b10. The ratio
of voltage V.sub.b10 and the current I.sub.B1o is the bioimpedance
Z.sub.b1o, which is processed in the microprocessor 64, as
described above, to compute the body fat percentage.
[0052] In the embodiment of the invention illustrated in FIGS. 1B,
4A and 4B, the body composition analyzer of the invention is
divided into two components, a base sensor unit 10b schematically
illustrated in FIG. 4A and a remote display unit 12b schematically
illustrated in FIG. 4B. The display unit 12b may, for example, be
mounted on the wall at the eye level of the user to permit the user
to more conveniently view the graphic display of his/her body
composition information.
[0053] The sensor unit 10b of FIG. 4A contains many of the
components included in the body composition analyzer unit of FIG.
3, and are identified by corresponding reference numerals to those
employed in FIG. 3. However, the graphical display 68 and key
matrix components are, in the embodiment of FIGS. 4A and 4B,
included in the remote display unit 12b, rather than in the sensor
unit. Also included in display unit 12b, rather than in the sensor
unit, is the beeper 74.
[0054] To allow the measured body composition information measured
and computed in the sensor unit 10b to be displayed in the remote
graphic display unit 12b, the sensor unit further includes a data
formatter 83, which receives the computed weight and body fat
percentage information from the output of microprocessor 64. Data
formatter 83 which modulates a carrier signal with the binary coded
data first received from the microprocessor.
[0055] The data sensor unit 10b also includes a data formatter 83,
which electrically alters the form of the coded data to achieve
increased efficiency of data transmission through a data
transmitter 85, which receives the encoded body composition data
from data formatter 83. Data transmitter 85, which transmits the
current and average body composition data to the remote display
unit 12b, preferably includes one or a plurality of infra-red (IR)
light-emitting diodes (LEDs) that convert the data to light. The
encoded body composition data transmitted from data transmitter 85
is received at the remote display unit 11 by an IR receiver 87. The
latter is coupled to a display microprocessor 89, which processes
that data and produces information signals to an LCD display 68,
which is similar to the one described above with reference to FIGS.
2 and 3.
[0056] The remote display unit 12b includes, as shown in FIG. 4B,
its own memory, here shown in the form of an EEPROM 91, that is
connected to the inputs of microprocessor 89 to store previously
computed trend body composition data and the relevant user data
that was entered in the key pad matrix switch array 80, which, in
the embodiment of FIG. 4B, is included in the display unit 12b. The
trend data and user data are transmitted between the EEPROM 91 and
microprocessor 84 via the SCL and SDA lines.
[0057] The remote display unit 12b includes its own battery pack 95
and power supply 97 to supply the operating voltages to the
microprocessor 89 and memory 91, as well as its own test and
calibrate interface 99. An LV detector 93 in the display unit 11
detects the occurrence of a low battery voltage level, and applies
a signal to microprocessor 89 when that occurs to provide an
indication at LCD display 68 of a low-voltage condition. LV
detector 93 sends a reset signal to the microprocessor 85 when the
batteries are removed or replaced in battery pack 95, or when the
battery voltage drops further below the low battery limit that
turns on the LCD indicator.
[0058] The operation of the body composition analyzer of FIGS. 4A
and 4B is similar to that of FIG. 3 except that the user's
information data is input by the use the keyboard matrix located in
the remote display unit, and the current and averaged body
composition information is displayed graphically at the remote
visual display unit. The user, as in the previously described
embodiment of FIG. 3, and as shown in FIG. 1B, stands on the heel
and toe electrodes 42, 44, 46 and 48 provided in the sensor unit
lob to provide the data which are processed by the microprocessor
to compute the user's body weight and bioimpedance using the data
from the sensor unit. From this data, the display unit
microprocessor 89 computes the user's body fat percentage as
described previously.
[0059] As described above, in addition to the user's current weight
and body fat percentage data, historical or trend data of these
body composition factors may also be displayed on the display unit.
This trend data is computed from body weight and body fat
percentage measurements that were taken previously at different
times over selected time periods, such as during eight consecutive
weeks, or eight months. As shown in FIG. 2, the trend data may be
displayed in a plurality of columns 30, 32 each of which represents
either an entire week or an entire month of the user's averaged
weight or body fat percentage. To this end, data of the current
body weight and body fat percentage measurements and a plurality of
prior body fat percentage and body weight measurements for up to
four different users is stored in memory 84. When any authorized
user operates the test display button 34, that stored prior body
measurement data is taken from memory and inputted to the
microprocessor 64. It is then displayed along with the authorized
user's current body weight and body fat percentage on bar graphs
30, 32.
[0060] At the onset of a typical use of the body composition
analyzer of the invention, the weight and body fat percentage trend
data for that user is displayed in a single bar, which represents
the user's average weight/body fat percentage for the first week.
After the first week, a second bar appears, which represents the
user's average weight/body fat percentage for the second week of
measurements. Each day during the second week in which a
measurement is taken, that day's values are averaged into the
totals for that week. This weekly trend continues until, say, the
ninth week, at which time the eight-week trend graph is collapsed
back into two bars. At this point, the data for the first four
weeks are averaged and converted into a bar for the first month,
and the data for the second four weeks of data are averaged and
converted into the second month bar. Successive measurements are
then averaged into the current month and additional month bars will
appear as time continues.
[0061] At the end of eight months, the data for the first month are
deleted and the data displays of all the subsequent months shift
down one position in the 1-8 bar graph (i.e. previous month 2 is
now shown in bar #1 position, and previous month 3 is now shown in
bar #2). In this way, the user always has an eight-month window in
which to graphically view his/her weight and body fat percentage
trends. It is to be noted that a missing measurement during one
specified interval that may affect the respective interval e.g.
week, is cancelled within the trend display so that missing
measurements do not adversely affect the overall trend
function.
[0062] As noted, the trend body fat percentage and body weight
information stored and displayed in the system of the invention are
averages for measurements made during a preselected period, such as
one week, the same period as the intervals between the bar graph
displays 30, 32. Thus, for example, if a user makes three
measurements of his/her body weight and body fat percentage during
week 1, the graphical data for that week on the display unit will
be the average of those three measurements of these measured body
components.
[0063] To this end, body weight and body fat percentage data, which
was measured and computed during a given week, in the manner
described above, are stored in memory 82. If an additional
measurement is performed during that same week, the previously
stored values of body weight and body fat percentage for that week
are recalled from memory 84, and an average of the previous and
current measurements is calculated in microprocessor 64. This
computed average value of body fat percentage and body weight are
stored in memory 84 for further display as trend data.
[0064] To achieve more accurate averaged data, the previously
stored values and the current values of body weight and body fat
percentage may be weighted by a suitable weighting factor depending
on the total number of measurements made during the one-week
interval. The weighting factor ensures that measurements of the
previously computed average value within one period are equally
weighted to the current measured value within the same period, e.g.
one week.
[0065] The following algorithm operated by software resident in
microprocessor 64 may be used to calculate the new average value to
be stored: 1 Y new = x i Y old + i i X
[0066] i--number of measurements
[0067] x--current measured value
[0068] Y.sub.new --calculated value to be stored
[0069] Y.sub.old --previously stored value
[0070] In order to perform this computation, the number i of
measurements made within the specified averaging period is also
stored in memory 82.
[0071] The trending bar graphs 30, 32, which, as noted,
respectively indicate the user's body weight and body fat
percentage, may, as shown in FIG. 2, be subdivided into eight
columns with 20 increments per column. Each of the columns
represents a measurement trend interval, e.g. either an entire week
or an entire month of averaged data, whereas each block in a column
represents a fixed quantity of body weight or body fat
percentage.
[0072] In an alternative procedure, body weight and body fat
percentage trend data may be computed in 3- to 8-week intervals.
That is, before week 3, no data is averaged and no trend is
displayed; after week 8, the oldest data is removed from the trend
display, e.g. week 1 is removed when week 9 is added; week 2 is
removed when week 10 is added, and so on. The weekly average may be
computed according to the following equation which is comparable to
the previous equation: 2 Weekly Avg . = ( Current Week s Average
.times. ( n - 1 ) ) + Data Just Measured n
[0073] Where n=number of measurements taken during the week
including the most recent one.
[0074] The weekly averages as thus computed may then be
mathematically "plotted" on a graph (i.e. these plots are used
algorithmically and not shown on the display). The graph of average
measurements would "appear" as points on a graph in which the week
number (e.g. 3-8) is plotted on the x-axis and the average value of
body data (weight and body fat percentage) is plotted on the
y-axis. A least squares algorithm could then be used to determine
the best fit of a line running through the "plotted" weekly
averages. This algorithm would yield the Y=mX+b equation for such a
line.
[0075] The slope m of this line indicates how much the weight or
body fat percentage is changing per week, whereas the offset b
indicates the weight or body fat percentage at week 0. Only the
value and direction of the slope, which indicates how much the
average is increasing or decreasing each week, need be calculated
such as by the use of the following equation:
[0076] 3 m = n ( n ( XY ) ) - ( n X ) ( n Y ) n ( n X 2 ) - ( n X )
2
[0077] Where m=the slope of the line
[0078] n=the number of points In the graph
[0079] X=the week number
[0080] Y=the data value (either the weight or body fat)
[0081] As a further alternative, instead of displaying the absolute
value of body fat percentage and body weight for each week and then
plotting those values on a graph, three general trends may be
indicated by three separate arrows on the LCD display.
[0082] In this trend display, an upward pointing arrow would
indicate that the body weight or body fat percentage is increasing;
a horizontal arrow would indicate that the data is stable; and a
downward pointing arrow would indicate that the data is
decreasing.
[0083] To aid a user in determining his/her progress, limits may be
specified for the combination of increasing/decreasing trends,
which may be skewed lower for the decreasing trend than for the
increasing trend or which may be equal for both increasing and
decreasing trends. In other words, the decreasing trend arrow would
be presented or illuminated for a smaller weight loss than would
the increasing trend arrow for a weight gain.
[0084] Body fat percentage trend is indicated, for example, as
follows. If the slope m is smaller than, e.g., minus 0.5 percent
per week (i. e. body fat percentage is decreasing more than 0.5
percent each week), the trend is decreasing and is shown on the LCD
display as a downward sloping arrow. If the slope is greater than,
e.g., 0.5 percent per week (body fat percentage is increasing more
than 0.5 percent each week), the trend is increasing and is shown
on the LCD display as an upward sloping arrow. All other slopes are
considered to be stable data values and are shown with a horizontal
arrow.
[0085] As a further option, weight trend can be indicated as
follows. If the slope is smaller than, e.g. minus 0.7 Kg per week
(i.e. weight is decreasing more than 0.7 Kg or equivalently 1.5 lbs
each week), the trend is considered to be decreasing and is shown
on the display as a downward sloping arrow. If the slope is greater
than e.g., 0.7 Kg per week (weight is increasing more than 0.7 Kg
or equivalently 1.5 lbs each week) the trend is considered to be
increasing and is shown on the LCD display as an upward sloping
arrow. All other slopes are considered to be stable data values and
are shown with a horizontal arrow.
[0086] The microprocessor 64 may be programmed further to determine
whether a body fat percentage or body weight measurement is
performed at a recommended period of time of day or window (e.g.
between 11:00 A.M. and 1:00 P.M.), and to store in memory 84 for a
later trend display only those values of body weight and body fat
percentage that were measured and computed during that
interval.
[0087] A measurement of body fat percentage or body weight, for
example, made at other times of the day will be displayed as
current data, but will not be stored for future trend display.
Alternatively, this value may be stored for future trend display if
the value is corrected for the time of day of the measurement as
described in the following section. This will ensure more reliable
and repeatable body fat percentage and body weight trend data since
the user's body fluid and electrolyte distribution and content,
which may significantly affect the measurements of those factors,
typically vary significantly during the day.
[0088] The algorithm used to compute body fat percentage from the
measured bioimpedance may further include a correction factor that
corrects for variations in the individual's measured weight, the
time of day the measurement is made, and the ratio of intra and
extracellular mass as measured by the computed bioimpedance. To
this end, as shown in FIG. 11, the algorithm selects a reference
time of day, say 4:00 p.m., and bioimpedance measurements taken at
other times of day are modified, such as by adding or subtracting
an offset or correction factor (impedance) from the current
bioimpedance measurement. That correction factor, which could
alternatively include a multiplying factor or any other function,
depends on the time of day the measurement was taken, e.g., as
shown in FIG. 11, 42 ohms at 8:00 a.m., 20 ohms at 11:00 a.m.,
etc.
[0089] In order to ensure privacy and security for the measured and
stored body composition data, microprocessor 64 may further include
a passive security algorithm, which compares, for example, the
measured body weight and a computed body composition factor, such
as body fat percentage, for a current user with the stored values
of these body compositions factors that were obtained previously
for authorized users of the system. If that comparison indicates
that the measured body weight or computed body fat percentage of
the current user differs from the previously measured values for
the corresponding body composition factors stored in the system
memory by more than a preset permissible deviation, say 5%, the
current user is denied access to any of the stored body composition
factors so that no stored or trend information will then be
displayed. The permitted deviation between the current and stored
values is preferably graduated so that a greater deviation is
permitted between current and stored values taken, say, a month or
two earlier, than would be permitted between a current and a prior
measurement taken only a week or two earlier.
[0090] The passive security algorithm may be modified, as described
below with reference to FIG. 9, to consider the personal
identification codes of authorized users, which are stored in, and
recognized by, the microprocessor 64. If a user enters an
identification code number and obtains a measurement of his/her
weight or body fat percentage, the algorithm compares these values
with the stored values of those body composition factors for the
user identified by the identification code entered by the current
user. If the current data is within a specified deviation, say 5
percent, of the stored data, the microprocessor 64 automatically
selects the correct personal data setting (e.g. height, sex, etc.)
for that user and permits access to the user's stored or trend
data. The permitted deviation between the current and the previous
measurements may be graduated, as described above, to reflect
increased periods between the dates of the current and prior body
composition measurements. If, on the other hand, the current and
stored values deviate by more than the predetermined, graduated
amount, the current user is prevented from gaining access to the
stored body composition data of the user whose ID code number was
entered.
[0091] The above-described authorization checking procedure may be
replaced, if desired, by a procedure that only checks the user's
identification. To this end, microprocessor 64 may include a
user-identification algorithm, which compares the user's current
body weight and/or body fat percentage (impedance) measurements
with previously stored values. Under this algorithm the
microprocessor then automatically selects the correct personal data
setting e.g. height, sex, etc., and/or former trend data or
measurement date for that individual if the current and stored
values deviate by not more than a predetermined amount. Thus, no
additional identification, e.g. ID code or password is necessary.
As an option, that information could also be requested, e.g. in
case of doubt, i.e. if the deviation is too high or too close to
the limit, or in case trend history data is to be used as well.
[0092] FIG. 7 illustrates the sequences that are taken at system
startup in which a first-time user enters his/her setup parameters.
The body composition analyzer is initially powered on and is in the
idle mode at 100. The user then holds the enter button 38 on the
base unit for at least 3 seconds as at 102. An indication such as
an audible beep is then made in the display unit at 104 to request
the user to enter the setup parameters.
[0093] At this time, through the operation of the up/down arrow
buttons 40, the user at step 106 selects the desired format for
displaying weight and height that is either in metric, i.e., kg,
cm, day, month, 24-hour time, or in English units, i.e. lbs, ft/in,
month/day, 12-hour time. The user again through the operation of
the up down buttons 40 then enters the date at 108 and the time at
110. Once these steps are completed, the body composition analyzer
returns to the idle mode of 112 and is now ready for use.
[0094] FIG. 8 illustrates the sequence of steps taken upon the
completion of the setup sequence illustrated in FIG. 7 for a number
of users (here four) to enter their personal identification data
into the base unit microprocessor for use in subsequent body
composition measurements. With the system in the idle mode at 112,
the new user presses one of the personal ID number buttons 16 (1-4)
that will thereafter be used each time the user makes a
measurement. The unit then requests the user, by the use of the
up/down buttons 40, to enter his/her height at 116, age at 118,
gender at 120, and fitness level (e.g. a number from 1 to 5) at
122.
[0095] Upon the completion of these steps, the trend display window
(typically two hours in duration) is set. As discussed previously,
this time window represents the period during which an authorized
user's measured body weight and body impedance values can be
considered valid for use in computing the trend body composition
averages. That is, data for measurements taken outside of this time
window are not stored in memory 84 for use in computing the user's
trend average. Stated differently, during regular use the user will
be able to trend his/her measured weight and body fat percentage
only if the body composition analyzer of the invention is used
during the two-hour time window. The beginning and end of the time
window is set at 124 by the operation of the up/down buttons
40.
[0096] After the completion of step 124, the user can then either
waive or select a two-number password at 126. If the user elects to
waive the use of a password, all subsequent measuring functions for
that user that would otherwise require the use of a password, as
described below with reference to FIG. 9 to carry out certain
functions such as trending display measurements, will not require
the user to insert a password. If the user wishes to select a
password to achieve increased security, that is done by the use of
the up/down buttons 40. Once this step is completed, the analyzer
unit will return to its idle state at 112.
[0097] If desired, if one of the steps 116-126 is not completed by
pressing the enter button 38 at a specified time, e.g. 15 seconds,
after entering the relevant information, the unit, as indicated at
130, will assume that the user wishes to abort the operation, and
the unit will return to the idle state without storing in its
memory any of the previously entered information.
[0098] FIG. 9 illustrates the sequence of steps taken to measure
and display current and trend body composition values both for an
authorized user and a guest user. The user stands on the base
sensor unit with his/her heels and toes in place for contact with
the stimulus and sense electrodes as shown at 132. The display
unit, as indicated at 134, then provides an audible ready beep and
displays the user's weight. If the user has previously obtained an
identification (ID) code number by carrying out the sequence of
steps described in FIG. 7 he/she then presses the appropriate ID
button 36, that is the button numbered 1, 2, 3 or 4 as at 136.
[0099] As a security and/or identification measure, the body
composition analyzer program may include a passive security feature
that permits the use of the system only by an authorized user. To
this end, the user's current measured body weight and body fat
percentage measurements are compared at 138 with the previous
measurements of those parameters for the user identified by the ID
number entered at step 136. If the user's current and previous
weight and body fat percentage measurements do not match, that is,
deviate by more than a significant amount, e.g. 5 percent, the unit
then inquires at 140, if the user identified by the entered ID
number had previously entered a password during the setup procedure
described in FIG. 7. If the answer to this inquiry is "yes," the
user is instructed at 142 to enter his/her previously established
two-digit password. If the password entered matches the user's
stored password, the analyzer system is instructed at 144 to
include these current measurements to compute the user's trend data
in the manner described above.
[0100] The LCD bar graph display 16, 18 displays at 146 the user's
current measured weight and body fat percentage as well as the
trend graphs for these body parameters. If the user had not
previously selected a password, the operating sequence proceeds
directly to the display step 146, which also occurs if a match
between current and previous measurements is found at step 138.
After a 30-second delay at 148 the display returns to its idle mode
at 150. If, after step 142, the user has not entered the correct
password, the display is cancelled and the system returns to its
idle mode at 150.
[0101] Non-registered users, or guests, can only measure their body
weight and body fat percentage. That is, since they have not
previously entered any of their personal information (height, age,
gender, fitness level, or password) into a pre-assigned ID number,
a guest cannot obtain trend data for his/her weight and body fat
percentage over time.
[0102] Measuring a guest's weight is accomplished in a manner
similar to that of an authorized user. That is, a guest presses the
guest ID button 35 at 152. If the guest wishes to view his/her
current body fat percentage, he or she is required to enter his/her
personal information (height, age, gender, fitness level) at
154.
[0103] Since the sensor unit has already measured the guest's
bioimpedance the entered personal information about the guest user
allows the unit to calculate that user's percent body fat
percentage, which information is displayed on the LCD graph display
18 as shown at 156. As in the case of an authorized user, after a
30-second delay at 148, the analyzer system returns to its idle
mode at 150.
[0104] There may be times when a user wishes to view his/her
previous measurements and the trend information that has been
previously accumulated and stored in memory. To do this, he/she
performs the steps illustrated in FIG. 10. As therein shown, the
user presses the display trend button 34 at 158 and then presses
the personal user ID button 36 that corresponds to the user's ID
number at 160.
[0105] If the user has previously selected a password, the unit
will prompt the user to enter that password at 164. If the correct
password has been entered, a graph of the past trend information is
displayed at 166 with the numerical values of the most recently
measured average body weight and average body fat percentage being
displayed at the top of the LCD display. The up-down arrow buttons
40 are then scrolled through the data for the previous weeks or
months, which will cause the bar for the currently displayed week
or month to become solid and the next week/month bar in the
succession to begin flashing in a "top-down fill" fashion. The
corresponding values for the bar will be displayed in the upper
half of the LCD display at 170.
[0106] For example, if the data shown on the LCD display includes a
graphical trend of eight months of data, pressing the down arrow
button 40 will cause the weight and body fat percentage graph
columns for month 8 to stop flashing. The weight and body fat graph
columns will then begin flashing in a "top down fill" mode, and the
numerical values for the weight and body fat percentage numerical
values for month 8 will be replaced with the average weight and
body fat percentage values for month 7.
[0107] If the user continues to press the down arrow button, the
weight and body fat percentage values for month 7 will be replaced
with that for month 6's body weight and body fat percentage values,
and month 7's columns will stop flashing while month 6's column
will begin flashing in the "top down fill" mode. The up arrow
button accomplishes the same function as the down arrow button, but
in the opposite chronological direction (i.e. the data/graphs for
month 1 would be shown first, followed by those for month 2,
etc.).
[0108] Once the user has completed his/her operation of the up/down
buttons 40, after a 30-second delay at 172 the display returns to
the idle mode at 174 in which only the time and date are displayed.
If an incorrect password is entered at step 164, the user's current
and trend data will not be displayed and the display is placed
directly into the idle mode.
[0109] In addition to displaying the user's body weight and percent
body fat percentage, the body composition analyzer of the invention
may, as noted above, also allows the user to view other body
composition factors such as lean body mass, his/her fat free mass
(FFM), body mass index (BMI), total body water, and blood pressure.
These values and their corresponding trend graphs may be displayed
on the LCD display in the same location as (i.e. they replace) the
body fat percentage values and trend chart, by toggling the button
24 through these three values.
[0110] That is, when the system is first used, body fat percentage
is displayed. If the user selects one of the other data formats
(fat free mass or body mass index) that new format will remain in
effect until it is changed by the operation of the %BF, FFM, BMI
button 24. For example, if a user takes his/her measurements and
presses button 24 (the LCD then displays weight and fat free mass),
the next time he/she takes a measurement or displays trend data,
the LCD display will automatically display both weight and fat free
mass.
[0111] It will be understood that the body composition analyzer of
the present invention, as described hereinabove, provides accurate
current and trend data of at least two selected body composition
factors, such as body fat percentage and body weight. It will be
further understood that modifications may be made to the described
embodiments of the invention without necessarily departing from the
spirit and scope of the invention.
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