Method, device and computer program product for monitoring the physiological state of a person

• US 20070265534A1
• Filed: 05/12/2006
• Published: 11/15/2007
• Est. Priority Date: 05/12/2006
• Status: Active Grant

• Current Assignee: Suunto Oy (Anta International Group Holdings Ltd.)
• Original Assignee: Suunto Oy (Anta International Group Holdings Ltd.)
• Inventors: Lindman, Erik, Martikka, Mikko
• Granted Patent: US 7,803,117 B2
• Time in Patent Office: Days
• US Class Current: 600/483
• 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, in which method

the heartbeat of the person is monitored in order to obtain a pulse signal, and

at least one parameter depicting the respiration of the person is determined on the basis of the periodicity of the temporal variation of the pulse data contained in the pulse signal, wherein

the periodicity of the temporal variation of the pulse data is determined with the aid of time stamps made of the basis of the pulse signal in the time domain.

2. The method according to claim 1, wherein the parameter depicting respiration is the respiratory frequency.

3. The method according to claim 1 or 2, wherein

a series comprising successive time points is formed from time stamps,

the period of the series is determined, and

parameter depicting respiration is determined on the basis of the period of the series.

4. The method according to claim 3, wherein the period of the series is determined by calculating the second derivative of the series and searching for its zeroes.

5. The method according to claim 1, wherein the parameter depicting respiration is used to estimate the person'"'"'s energy consumption.

6. The method according to claim 5, 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 is detected in the exercise, the estimate of the energy consumption is corrected towards the assumed real energy consumption.

7. The method according to claim 6, wherein the correction of the estimated energy consumption is boosted upwards, if the variable depicting the intensity of exercise is detected to increase and/or the calculated energy consumption is corrected downwards, if the variable depicting the intensity of exercise is detected to decrease.

8. The method according to claim 5, wherein the energy consumption is estimated on the basis of a higher degree behaviour, preferably of the second degree behaviour, of the respiratory frequency.

9. The method according to claim 5, wherein in the estimation of energy consumption, use is made of additionally at least one, typically 2-4, or all 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.

10. The method according to claim 5, wherein the estimation of energy consumption is based on the use of a determined parameter depicting respiration and only preliminary-data parameters underivable from metabolic tests.

11. The method according to claim 1, which is performed during exercise in a portable device, such as a wristop computer or a computer.

12. The method according to claim 1, which is performed partly or entirely in the device unit, such as the hear-rate belt, directly measuring the pulse signal.

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

a sensor for detecting the heartbeat in order to create a pulse signal or means for receiving pulse signal created with the aid of such a sensor, and

a processing unit for defining at least one parameter depicting respiration, on the basis of the periodicity of the temporal variation of the pulse date contained in the pulse signal, wherein

the processing unit is adapted to determine, in the time domain, the periodicity of the temporal variation of the pulse data, with the aid of time stamps made on the basis of the pulse signal.

14. The portable device according to claim 13, wherein the processing unit is adapted to determine the respiratory frequency.

15. The portable device according to claim 13 or 14, wherein the processing unit is adapted

to create, in a memory unit, a series comprising successive time points from the time stamps,

to determine the period of the series, and

to determine the parameter depicting respiration, on the basis of the period of the series.

16. The portable device according to claim 15, 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.

17. The portable device according to claim 13, which it is adapted to estimate the person'"'"'s energy consumption on the basis of the parameter depicting respiration.

18. The portable device according to claim 17, which is further adapted

to monitor temporal changes in some variable depicting the intensity of exercise, such as the respiratory frequency or heart rate, 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 towards the assumed real energy consumption.

19. The portable device according to claim 18, which is adapted to correct the energy consumption upwards in a boosted manner, if the variable depicting the intensity of the exercise is detected to increase and/or to correct the energy consumption downwards in a boosted manner, if the variable depicting the intensity of the exercise is detected to decrease.

20. The portable device according to claim 17, which is adapted to estimate the consumption of energy on the basis of higher degree behaviour, preferably the second-degree behaviour of respiration.

21. The portable device according to claim 17, which is adapted to use in addition at least one, typically 2-4, or all of the following preliminary data that can be entered in 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.

22. The portable device according to claim 17, which is adapted to estimate energy consumption by using parameters depicting respiration and only preliminary data parameters underivable from metabolic tests.

23. The portable device according to claim 13, which is a wristop computer or a computer.

24. The portable device according to claim 13, which is heart-rate belt.

25. A computer program product for determining the physiological state of a person, which is adapted to receive measurement information depicting the heartbeat of the person and to determine at least one parameter depicting the respiration of the person on the basis of the periodicity of the temporal variation of the pulse data contained in the measurement information in the time domain with the aid of time stamps made on the basis of pulse detections.

26. The computer program product according to claim 25, which is adapted

to create a series comprising successive time points from the pulse detections,

to determine the period of the series, for example, by calculating the second derivative of the series and searching for its zeroes, and

to determine a parameter depicting respiration on the basis of the period of the series.

27. The computer program product according to claim 25 or 26, which is further adapted to calculate an estimate of the person'"'"'s energy consumption by using the calculated parameter depicting respiration.

28. The computer program product according to claim 27, which is adapted, in addition to the parameter depicting respiration, to use only preliminary data parameters that are not derived from metabolic tests, preferably at least one, typically 2-4, or all of the following preliminary data parameters fed to it:

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.

29. The computer program product according to claim 27 or 28, 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 towards the assumed real energy consumption.