METHOD, DEVICE AND COMPUTER PROGRAM PRODUCT FOR MONITORING THE PHYSIOLOGICAL STATE OF A PERSON

• US 20100228134A1
• Filed: 05/03/2010
• Published: 09/09/2010
• Est. Priority Date: 05/12/2006
• Status: Active Grant

• Current Assignee: Suunto Oy (Anta International Group Holdings Ltd.)
• Original Assignee: Erik Lindman, Mikko Martikka
• Inventors: Lindman, Erik, MARTIKKA, Mikko
• Granted Patent: US 8,021,306 B2
• Time in Patent Office: Days
• US Class Current: 600/484
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/222 combined with detection or measurement of physiological parameters, e.g. heart rate

Abstract

The invention relates to a method, device, and computer program product for monitoring the physiological state of a person. In the method, the heartbeat of the person is detected in order to obtain a pulse signal, and at least one parameter depicting the respiration of the person is determined in the time domain with the aid of time stamps made of the basis of the pulse signal. With the aid of the method, it is possible to calculate an estimate of the person'"'"'s energy consumption during exercise, without complicated calculations or preliminary data based on measurements.

Claims

1. A method for monitoring the physiological state of a person during exercise using a portable computerized device, comprising

monitoring the heartbeat of the person in order to obtain heartbeat pulse signals, each heartbeat pulse signal having a maximum and minimum value and a duration or period, and wherein a pulse interval exists between consecutive pulse signals,

determining the respiratory frequency of the person i on the basis of the periodicity of the temporal variation of the pulse data contained in the pulse signal, and

determining the periodicity of the temporal variation of the pulse data using the portable computerized device, in the time domain by

time stamping pulses in the pulse signal,

forming a series of successive time points from the time stamps, and

determining the period of the series,

wherein the respiratory frequency is determined on the basis of the period of the series.

2. The method according to claim 1, wherein the period of the series is determined by calculating the second derivative of the series and searching for its zeroes.

3. The method according to claim 1, wherein the respiratory frequency is used to estimate the person'"'"'s energy consumption.

4. The method according to claim 3, wherein

the temporal changes in a variable depicting the intensity of the exercise, such as the respiratory frequency or heart rate, is monitored, in order to detect changes in rhythm taking place in the exercise, and

if a change in rhythm change is detected in the exercise, the estimate of the energy consumption is corrected to improve correspondence with an actual energy consumption.

5. The method according to claim 4, wherein the correction of the estimated energy consumption is corrected upwards, if the variable depicting the intensity of exercise is detected to increase and the calculated energy consumption is corrected downwards, if the variable depicting the intensity of exercise is detected to decrease.

6. The method according to claim 3, wherein the energy consumption is estimated on the basis of a second degree behaviour of the respiratory frequency.

7. The method according to claim 3, wherein in the estimation of energy consumption, use is made of additionally at least one of the following preliminary data:

the person'"'"'s activity class, the person'"'"'s weight, the person'"'"'s height, the person'"'"'s sex, the nature of the sport being played by the person.

8. The method according to claim 3, wherein the estimation of energy consumption is based on the use of a respiration frequency and only preliminary-data parameters underivable from metabolic tests.

9. The method according to claim 1, in which the steps of determining the respiratory frequency and determining the periodicity of the temporal variation of the pulse data are performed in a wristop computer during exercise.

10. The method according to claim 1, wherein the determining the respiratory frequency is performed in a heart-rate belt used to measure the pulse signal.

11. A portable device for monitoring the physiological state of a person during exercise, which device comprises

a sensor for detecting heartbeat in order to create a pulse signal or means for receiving a pulse signal created by such sensor, each heartbeat pulse signal having a maximum and a minimum value and a duration or period, and wherein a pulse interval exists between consecutive heartbeat pulse signals, and

a processing unit for determining the respiratory frequency of the person on the basis of the periodicity of the temporal variation of the pulse interval,

wherein the processing unit is adapted to determine in the time domain the periodicity of the temporal variation of the pulse data by

time stamping pulses in the pulse signal,

creating, in a memory unit, a series comprising successive time points from the time stamps, and

determining the period of the series,

and wherein the processing unit is adapted to determine the respiratory frequency on the basis of the period of the series.

12. The portable device according to claim 11, wherein the processing unit is adapted to determine the period of the series by calculating the second derivative of the series and searching for its zeroes.

13. The portable device according to any claim 11, which it is adapted to estimate the person'"'"'s energy consumption on the basis of the respiratory frequency.

14. The portable device according to claim 13, which is further adapted

to monitor temporal changes in a variable depicting the intensity of exercise in order to detect rhythm changes taking place in the exercise, and

if a change of rhythm is detected in the exercise, to correct the estimate of energy consumption to improve correspondence with an actual energy consumption.

15. The portable device according to claim 14, which is adapted to correct the energy consumption upwards, if the variable depicting the intensity of the exercise is detected to increase and to correct the energy consumption downwards, if the variable depicting the intensity of the exercise is detected to decrease.

16. The portable device according to claims 11, which is adapted to estimate the consumption of energy on the basis of second degree behaviour of the respiratory frequency.

17. The portable device according to claim 11, which is adapted to use in addition at least one of the following preliminary data fed to the device in order to estimate person'"'"'s energy consumption:

the person'"'"'s activity class, the person'"'"'s weight, the person'"'"'s height, the person'"'"'s sex, the nature of the sport being played by the person.

18. The portable device according to claim 11, which is adapted to estimate the persons energy consumption by using the respiratory frequency and only preliminary data parameters underivable from metabolic tests.

19. The portable device according to claim 11, which is a wristop computer or a computer containing means for wirelessly receiving a pulse signal from a pulse sensor.

20. A computer program product embodied in a tangible computer readable medium for causing a computer processor to perform a method for determining the physiological state of a person, which is adapted to receive measurement information comprising heartbeat pulse data of the person and to determine the respiratory frequency of the person on the basis of the periodicity of the temporal variation of said pulse data in the time domain by

time stamping pulses in the pulse data,

forming a series of successive time points from the time stamps,

determining the period of the series, and

determining the respiratory frequency on the basis of the period of the series.

21. The computer program product according to claim 20, which is adapted to determine the period of the series by calculating the second derivative of the series and searching for its zeroes.

22. The computer program product according to claim 20, which is further adapted to calculate an estimate of the person'"'"'s energy consumption by using the respiratory frequency.

23. The computer program product according to claim 22, which is adapted, in addition to the respiratory frequency, to use only preliminary data parameters that are not derived from metabolic tests.

24. The computer program product according to claim 22, which is adapted, on the basis of temporal changes in a variable depicting the intensity of the exercise, to correct the estimate of energy consumption to improve correspondence with an actual energy consumption.