Systems, devices and methods for continuous heart rate monitoring and interpretation

Abstract

Embodiments provide physiological measurement systems, devices and methods for continuous health and fitness monitoring. A lightweight wearable system is provided to collect various physiological data continuously from a wearer without the need for a chest strap. The system also enables monitoring of one or more physiological parameters in addition to heart rate including, but not limited to, body temperature, heart rate variability, motion, sleep, stress, fitness level, recovery level, effect of a workout routine on health, caloric expenditure. Embodiments also include computer-executable instructions that, when executed, enable automatic interpretation of one or more physiological parameters to assess the cardiovascular intensity experienced by a user (embodied in an intensity score or indicator) and the user's recovery after physical exertion (embodied in a recovery score). These indicators or scores may be displayed to assist a user in managing the user's health and exercise regimen.

What is claimed is: 
     
         1 . A wearable physiological measurement system, comprising:
 a wearable strap configured to be couplable to an appendage of a user, the wearable strap comprising:
 one or more light emitters for emitting light toward the user's skin, 
 one or more light detectors for receiving light reflected from the user's skin, 
 an electronic circuit board implementing a processing module configured for analyzing data corresponding to the reflected light to automatically and continually determine a heart rate of the user, and 
 a first set of one or more batteries for supplying electrical power to the one or more light emitters, the one or more light detectors and the electronic circuit board; and 
   a modular housing removably couplable to the strap, the modular housing comprising:
 a second set of one or more batteries chargeable by an external power source, the second set of batteries configured to recharge the first set of batteries in the strap; 
   wherein the combination of the first and second sets of batteries enables continuous monitoring of the heart rate of the user by the wearable strap.   
     
     
         2 . The wearable physiological measurement system of  claim 1 , wherein the modular housing further comprises:
 a visual display device configured to render a user interface for displaying an indication of the heart rate of the user.   
     
     
         3 . The wearable physiological measurement system of  claim 1 , wherein the modular housing further comprises:
 a global positioning system (GPS) sensor.   
     
     
         4 . The wearable physiological measurement system of  claim 1 , wherein the modular housing further comprises:
 a second electronic circuit board.   
     
     
         5 . The wearable physiological measurement system of  claim 1 , wherein the strap comprises one or more slots for removably coupling the first set of batteries to the strap. 
     
     
         6 . The wearable physiological measurement system of  claim 1 , wherein the strap comprises a storage device for storing the data corresponding to the reflected light. 
     
     
         7 . The wearable physiological measurement system of  claim 1 , wherein the strap comprises a wireless transmitter for transmitting the data corresponding to the reflected light to an external computational device. 
     
     
         8 . A wearable physiological measurement system, comprising:
 a wearable strap configured to be couplable to an appendage of a user, the wearable strap comprising:
 one or more light emitters for emitting light toward the user's skin, 
 one or more light detectors for receiving light reflected from the user's skin, and 
 an electronic circuit board comprising a plurality of electronic components configured for analyzing data corresponding to the reflected light to automatically and continually determine a heart rate of the user, the electronic circuit board comprising a processing module configured to:
 based on one or more signals associated with the heart rate of the user, detect an identity of a portion of the user's body to which the strap is coupled, and 
 based on the identity of the appendage, adjust data analysis of the reflected light to determine the heart rate of the user. 
 
   
     
     
         9 . The wearable physiological measurement system of  claim 8 , wherein the identity of the appendage is a wrist, an arm or an ankle of the user. 
     
     
         10 . The wearable physiological measurement system of  claim 8 , wherein the processing module is further configured to:
 determine that the strap is taken off from the user's body; and   if the strap is determined to be taken off from the user's body, deactivate the one or more light emitters and the light detectors and cease monitoring of the heart rate of the user.   
     
     
         11 . The wearable physiological measurement system of  claim 8 , wherein the identity of the user's body is determined based on an absorbance or reflectance level of the light emitted by the one or more light emitters to determine the position of the wearable system. 
     
     
         12 . The wearable physiological measurement system of  claim 8 , wherein the identity of the user's body is determined based on data collected from a motion sensor to determine the position of the wearable system. 
     
     
         13 . The wearable physiological measurement system of  claim 8 , wherein the identity of the user's body is determined based on data collected on the altitude of the wearable system to determine the position of the wearable system. 
     
     
         14 . A wearable physiological measurement system, comprising:
 a wearable strap configured to be couplable to an appendage of a user, the wearable strap comprising:
 one or more light emitters for emitting light toward the user's skin, 
 one or more light detectors for receiving light reflected from the user's skin, and 
 an electronic circuit board comprising a processing module configured for analyzing data corresponding to the reflected light to automatically and continually determine a sequence of instantaneous heart rate of the user; 
   wherein the processing module is configured to determine the heart rate of the user by:
 executing one or more computer-executable instructions associated with a peak detection algorithm to process the data corresponding to the reflected light to detect a plurality of peaks associated with a plurality of beats of the user's heart, 
 determining an RR interval based on the plurality of peaks detected by the peak detection algorithm, 
 determining a confidence level associated with the RR interval, and 
 based on the confidence level associated with the RR interval, selecting either the peak detection algorithm or a frequency analysis algorithm to process data corresponding to the reflected light to determine the sequence of instantaneous heart rates of the user. 
   
     
     
         15 . The wearable physiological measurement system of  claim 14 , wherein:
 based on a determination that the confidence level associated with the RR interval is above a predetermined threshold, the processing module uses the plurality of peaks to determine an instantaneous heart rate of the user; and   based on a determination that the confidence level associated with the RR interval is equal to or below the predetermined threshold, the processing module executes one or more computer-executable instructions associated with the frequency analysis algorithm to determine an instantaneous heart rate of the user.   
     
     
         16 . The wearable physiological measurement system of  claim 14 , wherein the processing module selects the peak detection algorithm or the frequency analysis algorithm regardless of a motion status of the user. 
     
     
         17 . The wearable physiological measurement system of  claim 14 , wherein the wearable strap further comprises a motion sensor for detecting a motion of the user, and wherein the frequency analysis algorithm processes the data corresponding to the reflected light based on the motion of the user. 
     
     
         18 . The wearable physiological measurement system of  claim 17 , wherein the motion sensor is an accelerometer. 
     
     
         19 . The wearable physiological measurement system of  claim 14 , wherein the processing module is further configured to determine a heart rate variability of the user based on the sequence of the instantaneous heart rates. 
     
     
         20 . The wearable physiological measurement system of  claim 14 , further comprising:
 a visual display device configured to render a user interface for displaying the sequence of the instantaneous heart rates of the user.   
     
     
         21 . The wearable physiological measurement system of  claim 14 , further comprising:
 a storage device configured to store the sequence of the instantaneous heart rates and the RR intervals determined by the processing module.   
     
     
         22 . A wearable physiological measurement system, comprising:
 a wearable strap configured to be couplable to an appendage of a user, the wearable strap comprising:
 one or more light emitters for emitting light toward the user's skin, 
 one or more light detectors for receiving light reflected from the user's skin, and 
 an electronic circuit board comprising a plurality of electronic components configured for analyzing data corresponding to the reflected light to automatically determine a heart rate of the user; 
   wherein the plurality of electronic components of the electronic circuit board are assembled as a multi-chip module within the strap such that a first set of the components is provided as a first electronic circuit board and a second set of the components is provided as a second electronic circuit board, and wherein one or more electrical connections are provided between the first and second electronic circuit boards.   
     
     
         23 . The wearable physiological measurement system of  claim 22 , wherein the first and second electronic circuit boards are vertically stacked within the strap such that the first electronic circuit board forms a first vertical layer of the multi-chip module proximal to the user's skin and the second electronic circuit board forms a second vertical layer of the multi-chip module distal to the user's skin. 
     
     
         24 . The wearable physiological measurement system of  claim 22 , wherein the first and second electronic circuit boards are horizontally displaced from each other within and along the strap. 
     
     
         25 . The wearable physiological measurement system of  claim 22 , wherein the strap includes one or more slots for removably adhering one or more batteries to the strap. 
     
     
         26 . The wearable physiological measurement system of  claim 22 , wherein the electronic circuit board comprises:
 a signal processing module configured to process one or more signals associated with the reflected light and/or associated with a motion of the user; and   a microcontroller configured to perform data analysis to automatically determine the heart rate of the user based on the one or more signals processed by the signal processing module.   
     
     
         27 . A wearable physiological measurement system, comprising:
 a plurality of light emitters for emitting light toward the user's skin;   a plurality of light detectors for receiving light reflected from the user's skin;   a motion sensor for detecting a motion of the user; and   a processing module configured to:
 determine a motion status of the user based on data received from the motion sensor, and 
 based on the motion status of the user, automatically and selectively activate one or more of the light emitters to determine a heart rate of the user. 
   
     
     
         28 . The wearable physiological measurement system of  claim 27 , wherein the processing module is further configured to:
 upon determining that the motion status indicates that the user is in motion, selectively activate a first set of one or more light emitters and at least one of the light detectors to perform optical measurement of a pulse rate at the user's skin; and   upon determining that the motion status indicates that the user is at rest or at sleep, selectively activate a second set of one or more light emitters and at least one of the light detectors to perform optical measurement of the pulse rate at the user's skin;   wherein the second set of one or more light emitters emits light at a longer wavelength than the first set of light emitters.   
     
     
         29 . The wearable physiological measurement system of  claim 27 , further comprising:
 a piezo-sensor for detecting a pulse rate at the user's skin.   
     
     
         30 . The wearable physiological measurement system of  claim 29 , wherein the processing module is further configured to:
 upon determining that the motion status indicates that the user is in motion, selectively activate at least one of the light emitters and at least one of the light detectors to perform optical measurement of the pulse rate at the user's skin; and   upon determining that the motion status indicates that the user is at rest or at sleep, selectively activate the piezo-sensor to detect the pulse rate at the user's skin.   
     
     
         31 . The wearable physiological measurement system of  claim 27 , wherein the one or more of the light emitters are selectively activated based on historical data corresponding to the user. 
     
     
         32 . The wearable physiological measurement system of  claim 31 , wherein the historical data corresponds to a habit of the user. 
     
     
         33 . A wearable physiological measurement system, comprising:
 a plurality of light emitters for emitting light toward the user's skin;   a plurality of sensors, comprising:
 a plurality of light detectors for receiving light reflected from the user's skin, and 
 a motion sensor for detecting a motion of the user; and 
   a processing module configured to determine a heart rate of the user based on light received by one or more of the light detectors, wherein the processing module is further configured to:
 process one or more signals generated by at least one of the sensors, and 
 based on the one or more processed signals, automatically adjust an operational characteristic of one or more of the light emitters and/or one or more of the light detectors to minimize consumption of power by the wearable physiological measurement system. 
   
     
     
         34 . The wearable physiological measurement system of  claim 33 , wherein the processing module is configured to:
 process the one or more signals to determine a motion status of the user; and   adjust a duty cycle of the one or more light emitters and a corresponding sampling rate of the one or more light detectors based on the motion status of the user.   
     
     
         35 . The wearable physiological measurement system of  claim 34 , wherein the processing module is configured to:
 upon determining that the motion status indicates that the user is at a first level of motion, activate the one or more light emitters at a first duty cycle and sample the reflected light using the one or more light detectors at a first sampling rate; and   upon determining that the motion status indicates that the user is at a second lower level of motion, activate the one or more light emitters at a second duty cycle and sample the reflected light using the one or more light detectors at a second sampling rate;   wherein the second sampling rate is lower than the first sampling rate and the second duty cycle is lower than the first duty cycle.   
     
     
         36 . The wearable physiological measurement system of  claim 35 , wherein the first level of motion is exercise, and wherein the second level of motion is sleep or rest. 
     
     
         37 . The wearable physiological measurement system of  claim 35 , wherein the first level of motion is light motion, and wherein the second level of motion is sleep or rest. 
     
     
         38 . The wearable physiological measurement system of  claim 33 , wherein the processing module is configured to:
 process the one or more signals to determine a motion status of the user; and   based on the one or more processed signals, automatically adjust power consumption by the one or more light emitters by adjusting a duty cycle of the one or more light emitters and/or adjusting a current supplied to the one or more light emitters.   
     
     
         39 . The wearable physiological measurement system of  claim 33 , wherein the processing module is configured to:
 process the one or more signals to determine a characteristic of the reflected light detected at the one or more light detectors; and   based on the one or more processed signals, automatically adjust a current supplied to the one or more light emitters.   
     
     
         40 . The wearable physiological measurement system of  claim 39 , wherein the characteristic of the reflected light indicates an ambient light condition and/or an optical characteristic of the user's skin. 
     
     
         41 . The wearable physiological measurement system of  claim 33 , further comprising a wireless transmitter, and wherein the processing module is further configured to:
 determine an amount of data to be transmitted to an external computational device; and   based on the amount of data to be transmitted, automatically adjust a data transmission rate from the wearable physiological measurement system to the external computational device.   
     
     
         42 . The wearable physiological measurement system of  claim 41 , wherein the amount of data to be transmitted is based on an amount of data collected by the system since a time when data was last transmitted from the wearable physiological measurement system. 
     
     
         43 . The wearable physiological measurement system of  claim 41 , wherein physiological data associated with the user is transmitted from the wearable physiological measurement system to the external computational device when the amount of data to be transmitted exceeds a predetermined threshold. 
     
     
         44 . The wearable physiological measurement system of  claim 33 , further comprising a wireless receiver and a wireless transmitter, and wherein the processing module is further configured to:
 use wireless receiver to detect an external computational device in proximity to the wearable physiological measurement system; and   automatically initiate transmission of physiological data associated with the user from the wearable physiological measurement system to the external computational device using the wireless transmitter.   
     
     
         45 . The wearable physiological measurement system of  claim 33 , wherein the operational characteristic is adjusted based on historical data corresponding to the user. 
     
     
         46 . The wearable physiological measurement system of  claim 45 , wherein the historical data corresponds to a habit of the user. 
     
     
         47 . A computer-executable method for determining an indicator of cardiovascular intensity experienced by a user, the method comprising:
 programmatically receiving, using a computer system, data corresponding to heart rate of a user during an exercise routine;   transforming the heart rate data to a time series of heart rate reserve data using a processing module of the computer system;   weighting the heart rate reserve data according to a weighting scheme using the processing module of the computer system;   programmatically generating, using the processing module of the computer system, an indicator of cardiovascular intensity based on the weighted heart rate reserve data; and   displaying, on a user interface rendered on a display device of the computer system, the indicator of cardiovascular intensity.   
     
     
         48 . The method of  claim 47 , wherein the weighting scheme uses a trained machine learning system implementing a machine learning algorithm embodied on one or more computer-readable media, the machine learning system trained to correlate heart rate data to cardiovascular intensities. 
     
     
         49 . The method of  claim 48 , wherein the trained machine learning algorithm is retrained to adjust perceived difficulties of exercise routines as the user's fitness improves. 
     
     
         50 . The method of  claim 47 , wherein the weighting scheme accounts for cardiovascular efficiencies at different intensity levels. 
     
     
         51 . The method of  claim 47 , further comprising:
 displaying qualitative information associated with the intensity score.   
     
     
         52 . The method of  claim 51 , wherein the qualitative information comprises one or more of:
 an indication of whether the user exceeded the user's anaerobic threshold during the exercise routine;   an indication of whether the user is likely to experience muscle soreness;   an indication of a level of recovery required after the exercise routine; and   an indication of one or more future alterations to the exercise routine that is required based on one or more health-related goals of the user.   
     
     
         53 . The method of  claim 47 , wherein the indicator corresponds to a perceived difficulty of the exercise routine by the user, the method further comprising:
 displaying, on the user interface, the perceived difficulty of the exercise routine.   
     
     
         54 . The method of  claim 47 , further comprising:
 based on the indicator of the intensity of the exercise, automatically altering an exercise plan according to one or more health goals of the user; and   displaying, on the user interface, the altered exercise plan.   
     
     
         55 . The method of  claim 47 , further comprising:
 programmatically receiving data corresponding to heart rate of a second user during an exercise routine;   transforming the heart rate data to a time series of heart rate reserve data;   weighting the heart rate reserve data according to a weighting scheme;   programmatically generating a second indicator of cardiovascular intensity based on the weighted heart rate reserve data; and   displaying, on the user interface rendered on a display device, the indicator corresponding to the first user and the second indicator corresponding to the second user.   
     
     
         56 . The method of  claim 55 , wherein the heart rate data of the first and second users are obtained from different user-selected time periods. 
     
     
         57 . A computer-executable method for determining an indicator of physical recovery of a user, the method comprising:
 programmatically receiving a heart rate variability of a user using a computer system;   programmatically receiving a resting heart rate of the user using the computer system;   programmatically receiving a sleep quality indicator of the user using the computer system;   programmatically generating, using a processing module of the computer system, a recovery indicator of physical recovery of the user based on the heart rate variability, the resting heart rate and the sleep quality indicator; and   displaying, on a user interface rendered on a visual display device of the computer system, the recovery indicator.   
     
     
         58 . The method of  claim 57 , wherein the sleep quality indicator is determined using one or more of: a duration of sleep, a level of movement of the user during sleep and a number of times the user woke up during sleep. 
     
     
         59 . The method of  claim 57 , wherein the indicator corresponds to a perceived strain of an exercise routine performed by the user, the method further comprising:
 displaying, on the user interface, the perceived strain of the exercise routine.   
     
     
         60 . The method of  claim 57 , wherein the indicator corresponds to a perceived psychological strain experienced by the user, the method further comprising:
 displaying, on the user interface, the perceived psychological strain.   
     
     
         61 . The method of  claim 57 , further comprising:
 displaying, on the user interface, qualitative information on the user's health corresponding to the indicator.   
     
     
         62 . The method of  claim 61 , wherein the qualitative information comprises one or more of:
 an indication of whether the user has physically recovered from an exercise routine;   an indication of whether the user has psychologically recovered from an exercise routine;   an indication of whether the user requires rest;   an indication of whether the user is prepared for future activity; and   an indication of one or more future alterations to an exercise routine that is required based on one or more health-related goals of the user.   
     
     
         63 . The method of  claim 61 , further comprising:
 based on the indicator, automatically altering an exercise plan according to one or more health goals of the user; and   displaying, on the user interface, the altered exercise plan.