WO2018118703A1

WO2018118703A1 - Device, method and system for fitness level monitoring using continuous lactate monitoring device

Info

Publication number: WO2018118703A1
Application number: PCT/US2017/066772
Authority: WO
Inventors: Benjamin Jay Feldman; Hyun Cho; Tianmei Ouyang; Kuan-Chou Chen; Udo Hoss
Original assignee: Abbott Diabetes Care Inc
Current assignee: Abbott Diabetes Care Inc
Priority date: 2016-12-23
Filing date: 2017-12-15
Publication date: 2018-06-28
Anticipated expiration: 2019-06-23

Abstract

Method, device and system for providing fitness level indication metric using continuously monitored lactate level fluctuation from a lactate monitoring device, lactate peak level information, and/or calories expended information are disclosed.

Description

DEVICE, METHOD AND SYSTEM FOR FITNESS LEVEL MONITORING USING CONTINUOUS LACTATE MONITORING DEVICE

BACKGROUND

[0001] The detection and/or monitoring of lactate levels or other analytes, such as glucose, oxygen, AIC, or the like, in certain individuals is vitally important to their health. Anaerobic metabolism during strenuous exercise produces lactate. The amount of lactate produced by the body depends upon the intensity or severity and duration of the physical exercise, as well as the level of aerobic fitness of the person. Typically the body of a fit person performing a predetermined exercise routine such as a bike ride over a 2 hour time period will produce less lactate than the body of a less fit person who performs the same predetermined exercise routine.

[0002] Athletes and those that desire monitoring physical fitness levels do not presently have tools that allow for simple, robust lactate based fitness level monitoring. With the development of lactate monitoring devices and systems that provide real time lactate level information in a convenient and painless manner, there is an ongoing desire to integrate such monitoring devices and systems into daily life to obtain health related measurements. More specifically, there is a strong desire to identify the impact of daily activities such as exercise, medication administration, meal consumption and so forth on lactate level fluctuation and provide information regarding the fitness level to take proactive actions. Furthermore, there is a desire to convey this information to users via personal computing devices, such as via interfaces and indicators.

SUMMARY

[0003] Embodiments of the present disclosure include method, device and system for determining fitness level information based on continuously monitored lactate level fluctuation information for an activity period (user defined, or system/device detected) received, for example, from an in vivo continuous lactate sensor in fluid contact with bodily fluid such as dermal fluid or interstitial fluid, and based on information pertaining to amount of calories expended during the activity period (manually provided or entered by a user, determined using, for example, heart rate information). Embodiments of the present disclosure include determining the fitness level information using an integrated lactate amount during the activity period which includes, for example, determining the area under the curve defined by the lactate level fluctuation information over the activity period, or peak lactate level over the activity period.

[0004] Among other embodiments, the systems and devices disclosed herein provide for exercise monitors to calculate and output a body's response to exertion as one or more measures of fitness. In comparison, prior exercise monitors have not calculated the body's response to said exertion.

[0005] In certain embodiments, the fitness level information is determined by dividing the determined amount of calories expended, by the integrated lactate amount during the activity period, where the integrated lactate amount includes the area under the curve defined by the continuously monitored lactate level during the activity period. In other embodiments, the fitness level information is determined by dividing the determined amount of calories expended, by a peak lactate level determined during the activity period. The smaller the lactate excursion for a given calorie amount expended, the more fit the person performing the exercise during the activity period.

[0006] Embodiments of the present disclosure include an overall network with sensor based devices in communication with a data receiver (e.g., smart phone, smart watch, wearable fitness monitor etc.) with programming to process the continuously monitored real time lactate level fluctuation information and calories expended information to determine fitness level. Optionally, a data communication network is provided with one or more back-end server terminals that includes a network cloud configuration and configured to either execute the functions of the data receiver for fitness level analysis when in direct data communication with the sensor based devices, and provide the results of the analysis to the data receiver, or configured to operate in a passive configuration performing data backup functions or data repository functions for the data receiver and/or the sensor based devices.

[0007] Embodiments also optionally include one or more medication devices such as an insulin pump or an insulin injector pen that is configured to receive analysis data from the smart phone, from the one or more back-end server terminals, or directly from the sensor based devices. [0008] In an embodiment, a computing device receives the calories expended in an exercise session, measures and determines the lactate amount produced over that same exercise session, and combines the two measurements to produce and output at least one measure of fitness. The computing device is configured to calculate and display numerous kinds of measures of fitness for the user, and to provide such measures in comprehensible manners for a user.

[0009] These and other features, objects and advantages of the present disclosure will become apparent to those persons skilled in the art upon reading the details of the present disclosure as more fully described below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG.1 is an overall system for providing a fitness monitor using continuous lactate monitoring device in accordance with one embodiment of the present disclosure;

[0011] FIG. 2 is a block diagram of the analysis module of FIG. 1 in accordance with one embodiment of the present disclosure;

[0012] FIG. 3 is a flowchart illustrating a routine to determine fitness level during an activity period using continuous lactate sensor in accordance with one embodiment of the present disclosure;

[0013] FIG. 4 is a flowchart illustrating fitness level analysis of FIG. 3 using

continuous lactate sensor in accordance with one embodiment of the present disclosure;

[0014] FIG. 5 is a flowchart illustrating fitness level analysis of FIG. 3 using

continuous lactate sensor in accordance with another embodiment of the present disclosure;

[0015] FIG. 6 is an exemplary graph illustrating lactate level excursion during an activity period using a continuous lactate monitor in accordance with one embodiment of the present disclosure. DETAILED DESCRIPTION

[0016] Before the present disclosure is described in detail, it is to be understood that this disclosure is not limited to particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.

[0017] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the disclosure. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges as also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure.

[0018] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present disclosure, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited.

[0019] It must be noted that as used herein and in the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

[0020] The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present disclosure is not entitled to antedate such publication by virtue of prior disclosure. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed. [0021] As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete

components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present disclosure.

[0022] The figures shown herein are not necessarily drawn to scale, with some

components and features being exaggerated for clarity.

[0023] FIG.1 is an overall system for providing a fitness monitor using continuous lactate monitoring device in accordance with one embodiment of the present disclosure. Referring to FIG. 1, the system for providing a fitness monitor using continuous lactate monitoring device 100, in certain embodiments, includes a data receiver 110 (e.g., mobile phone, personal digital assistant (PDA), smart watch, wearable fitness device) including user interface 110A and analysis module HOB programmed in the data receiver 110, for example, installed as a downloaded executable file over data network 140 from server 150. As discussed in further detail below, in certain embodiments, analysis module 110B is configured to receive the real time continuous lactate level fluctuation information and calories expended information during an activity period, to perform the fitness level analysis based on the received real time continuous lactate level fluctuation information and calories expended information during the activity period, and to generate the determined fitness level information for output on the user interface 110A.

[0024] Referring back to FIG. 1, also shown are lactate monitor 130A, calorie monitor 130B, and activity monitor 130C each in data communication with the data receiver 110, or alternatively or in addition to, each in data communication with server 150 over data network 140. In certain embodiments, lactate monitor 130A includes a lactate sensor described in more detail in U.S. Provisional Application No. 62/175,910 filed on June 15, 2015, assigned to the assignee of the present application, the disclosure of which is incorporated by reference for all purposes. In certain embodiments, activity monitor 130C includes one or more of a heart rate monitor, a gyroscope, an accelerometer, an altitude monitor, a pedometer, a thermometer, an atmospheric pressure monitor, and any other monitors or sensors associated with physical activity.

[0025] Referring to FIG. 1, in certain embodiments, monitors 130A, 13 OB, 130C are programmed to communicate the monitored information to server 150 for storage and/or analysis, or to data receiver 110 for storage, analysis, and subsequent communication of either or both raw data received from each monitor 130A, 130B, 130C, and/or processed data or information from each monitor 130A, 130B, 130C to server 150 over data network 140 for storage and/or further analysis.

[0026] Referring still to FIG. 1, also shown in the system for providing the fitness monitor using continuous lactate monitoring device 100 is medication delivery device 120 in data communication with data receiver 110, server 150, and/or one or more of the monitors 130A, 130B, 130C over data network 140. While not shown, in certain embodiments, the operation of the routines and functions of the software or algorithm programmed in data receiver 110 may be implemented in medication delivery device 120 where medication delivery device 120 directly receives data or information from one or more of the monitors 130A, 130B, 130C, and performs fitness level

determination analysis, and, for example, modifies a medication delivery profile (e.g., basal insulin delivery rate, determine a bolus insulin dose amount).

[0027] In certain embodiments, data receiver 110 includes one or more monitors 130A, 130B, 130C integrated within the data receiver 110. For example, a smart watch configured as a data receiver 110, in certain embodiments, incorporates a lactate monitor and/or a heart rate monitor. In certain embodiments, the smart watch data receiver 110 is also configured to incorporate a glucose sensor - in vivo, dermal, transdermal, or optical, such that real time monitored glucose level information is obtained for further analysis.

[0028] FIG. 2 is a block diagram of the analysis module of FIG. 1 in accordance with one embodiment of the present disclosure. Referring to FIG. 2, analysis module HOB of data receiver 110 includes data input interface 111 for interfacing or receiving data input from one or more monitors 130A, 130B, 130C external to data receiver 110 or internal and within data receiver 110. Data and/or information received via data input interface 111 are provided to fitness monitoring unit 112. In certain embodiments, fitness monitoring unit 112 processes the real time continuously monitored lactate level fluctuation information from lactate monitor 130A (FIG. 1), and the calorie expended information from calorie monitor 13 OB for an activity period to perform fitness level analysis, and to generate the determined fitness level information to present to the user.

[0029] Referring back to FIG. 2, in certain embodiments, the output of fitness

monitoring unit 112 is provided to data output interface 113 which is operatively coupled to user interface 11 OA of data receiver 110 for display, output or otherwise notification or prompt to the user of data receiver 110 that the fitness level determination has been completed based on, for example, the received continuously monitored lactate fluctuation level and the calories expended information during the activity period.

[0030] FIG. 3 is a flowchart illustrating a routine to determine fitness level during an activity period using continuous lactate sensor in accordance with one embodiment of the present disclosure. Referring to FIG. 3, with the detection of an activity commencement, a timer in data receiver 110 (FIG. 1) for example is triggered, and upon the conclusion of the activity, the timer is stopped to define the activity start and end time, hereinafter the activity period (310). In certain embodiments, the activity start and end times may be manually input to the data receiver 110. In certain embodiments, the data receiver 110 is configured to detect movement of the data receiver 110 (worn by the user as a smart watch or a wearable fitness monitor, for example) and prompts the user to confirm the start of an activity. Similarly, when the data receiver 110 detects lack of movement of the data receiver 110, the data receiver 110, in certain embodiments, prompts the user to confirm the end of the activity.

[0031] Referring to FIG. 3, during the determined activity period (310), in certain embodiments, the lactate level fluctuation is monitored in real time and recorded with a corresponding time stamp (320). For example, in certain embodiments, lactate monitor 130A (FIG. 1) is configured to generate a series of time spaced signals corresponding to the monitored lactate level and communicates the lactate signals to the data receiver 110 (for storage/further processing). Also, the amount of calories expended during the activity period is determined (330) as calories information for the activity period. For example, calorie monitor 13 OB (FIG. 1), in certain embodiments, is configured to determine the amount of calories expended during the activity period and communicates the calories information to the data receiver 110 (FIG. 1) for storage and analysis. In certain embodiments, calories information may be manually input to data receiver 1 10 using the user interface 110A (FIG. 1) based on one or more physiological parameters of the user such as the user's body weight information, and the intensity or the level of strenuousness of the underlying activity during the activity period.

[0032] In certain embodiments, the lactate level fluctuation information determination (320) and the calories determination (330) are performed simultaneously, or alternatively, serially as long as at the end of the activity period, both the continuously monitored lactate level fluctuation information over the activity period and the calories information during the activity period are provided to the data receiver 110 (FIG. 1). Referring again to FIG. 3, data receiver 110, in certain embodiments, performs fitness level analysis (340) using the monitored real time, lactate level information (320) and the determined calories (calories information) during the activity period (330), and generates and outputs the determined fitness level information or metric (350).

[0033] FIG. 4 is a flowchart illustrating fitness level analysis of FIG. 3 using

continuous lactate sensor in accordance with one embodiment of the present disclosure. An embodiment as illustrated in FIG. 4 may be implemented using one or more features illustrated by FIGS. 1 and 2, and reference is made to one or more illustrated features.

[0034] Embodiments recognize that types of health information, such as calorie information, may be more measured via sensors, received via user input, or otherwise obtained for use. As such, referring to FIG. 4, in certain embodiments, data receiver 110 (FIG. 1) retrieves the calories information for the activity period received from calorie monitor 130B (FIG. 1) (410), and determines an integrated lactate amount during the activity period (420). In certain embodiments, the integrated lactate amount during the activity period is determined by calculating the area under the curve defined by the continuously monitored lactate fluctuation level during the activity period. Thereafter, the fitness level information or metric is determined by dividing the calories expended (from the calories information), indicating the amount of calories burned during the activity period (in units of calories, for example), by the integrated lactate amount during the activity period (in units of mM lactate * minutes) (430). A fitness level indicator corresponding to the determined fitness level information or metric is thereafter output to the user (440).

[0035] FIG. 5 is a flowchart illustrating fitness level analysis of FIG. 3 using

continuous lactate sensor in accordance with another embodiment of the present disclosure. An embodiment as illustrated in FIG. 5 may be implemented using one or more features illustrated by FIGS. 1 and 2, and reference is made to one or more illustrated features.

[0036] Embodiments recognize the existence and use of sensors for measuring lactate concentrations. As such, compared to the routine described above in conjunction with FIG. 4, the embodiment in FIG. 5 determines the peak lactate level during the activity period (520) from the continuously monitored lactate fluctuation level information from lactate monitor 130A (FIG. 1), and divides the calories expended during activity period (510) (in units of calories, e.g.) with the determined peak lactate level during the activity period (in units of mM lactate * minutes) to determine the corresponding fitness level information/metric (530), and to output the corresponding fitness level indicator (540) associated with the determined fitness level information/metric.

[0037] In the manner described above, in certain embodiments, data receiver 110 (FIG.

1) is configured to determine a metric for the level of fitness of a person based on the real time continuously monitored lactate fluctuation level information during the time the person is exercising, for example in conjunction with calories burned during the exercise. In certain embodiments, the fitness level indication information is determined by dividing the calories burned or expended during the activity period by either the integrated lactate amount during the activity period or by the peak lactate level during the activity period.

[0038] FIG. 6 is an exemplary graph illustrating lactate level excursion during an activity period using a continuous lactate monitor in accordance with one embodiment of the present disclosure. More specifically, a bicycle ride was performed wearing a dermal lactate sensor (as described more fully in U.S. Provisional Application No. 62/175,910, the disclosure of which is incorporated herein by reference for all purposes) which continuously monitored the lactate level in dermal fluid of the cyclist during the bicycle ride. The bicycle ride included a trip route of approximately 60 minutes at a speed of approximately 10 mph.

[0039] The lactate response curve illustrating the lactate level fluctuation during the bicycle ride is shown in FIG. 6. As can be seen from FIG. 6, each of the two bike excursions (outbound and inbound) generated a consistent response in lactate level fluctuation. The peak lactate level was measured at approximately 5.8 mM lactate for both the outbound and inbound bicycle ride during this activity period. The integrated lactate amount for the outbound bicycle ride was approximately 67 mM lactate * minutes, while for the inbound bicycle ride, it was approximately 89 mM lactate * minutes. In one embodiment, the integrated lactate amount is determined by calculating the area under the curve shown in FIG. 6.

[0040] For the bicycle ride referenced in conjunction with FIG. 6, given the cyclist's body weight of 175 pounds, 30 minutes of cycling at a speed of approximately 8-13 mph resulted in 196 calories expended for each outbound and inbound portions of the ride. With the information determined above, the fitness level indicator is determined in one embodiment by dividing the total calories expended during the ride of 392 calories (= 196 calories * 2) by the peak lactate level detected during the bike ride (5.8mM lactate) resulting in a fitness level metric of 67.6. In another embodiment, the fitness level indicator is determined by dividing the total calories expended during the ride (392 calories) by the integrated lactate amount during the ride of 156 mM lactate * minutes (67 mM lactate * minutes for outbound added to 89 mM lactate * minutes inbound) resulting in a fitness level metric of 2.5.

[0041] As described above, and given that the amount of lactate produced during the activity is less for a more fit person, it can be seen that a fitness level metric value greater than 67.6 (peak lactate approach) or the fitness level metric value greater than 2.5 (integrated lactate approach) for the hour long bicycle ride described above would indicate a physiological profile that is more fit than the profile of the person performing the bicycle ride described above in conjunction with FIG. 6. [0042] Numerous embodiments provide for the physiological profile, once determined, to be provided to the user. In embodiments, a computing device is configured to determine and display the fitness level metric value. In order to provide the fitness level metric value so it may be easily understood, an indicator is displayed which corresponds to the fitness level metric. In an embodiment, the indicator may be a color assigned to a range for the fitness level metric and corresponding to an overall fitness description (e.g., green for "fit", yellow for "less fit"). In another embodiment, the indicator corresponds to a numerical value assigned to a range of fitness levels. The fitness descriptions may be relative to the user or some other population.

[0043] In the manner described, in accordance with the embodiments of the present disclosure, using a lactate monitor that continuously monitors the lactate level fluctuation in real time, and with the ability to detect the peak lactate level during a defined activity period, a person can monitor his or her fitness level while engaging in the same activity. For example, for a cyclist who rides his bicycle along the same route three times weekly, each ride lasting 2 hours and covering 25 miles in distance with approximately 900 feet of climbing, and wearing the lactate and calorie monitors 130A, 130B, the fitness monitoring based on continuous lactate fluctuation monitoring in accordance with the embodiments of the present disclosure informs the cyclist of progress in improving his or her fitness level. More specifically, by comparing the fitness level indicator between each bicycle ride, the cyclist can determine whether his or her fitness level is improving. Such information is useful for the cyclist for health management and monitoring, as well as for training and/or competing in cycling events by monitoring the fitness level and using the fitness level indicator for training or competing in cycling events.

[0044] For example, in certain embodiments, a pattern based on fitness level metric values can be identified based on continuously monitoring lactate fluctuation level, where for example, an increasing fitness level metric value for bicycle rides indicates that the cyclist's physiology is improving. On the other hand, when a pattern of fitness level metric values demonstrate a continuing decrease in the fitness level metric values, the cyclist is made aware of the need to improve physiological condition (e.g., improved diet, strength conditioning, additional cardiovascular exercise) to maintain or improve his or her fitness level metric values.

[0045] Accordingly, a method of determining a fitness level during an activity period includes determining an amount of calories expended during an activity period, receiving lactate level fluctuation information from a lactate sensor during the activity period, performing a fitness level analysis based on the amount of calories expended and the received lactate level fluctuation information, and determining a fitness level metric based on performing the fitness level analysis.

[0046] In certain embodiments, performing fitness level analysis includes determining an integrated lactate amount during the activity period, where determining the integrated lactate amount includes determining the area under the curve defined by the lactate level fluctuation information over the activity period.

[0047] In certain embodiments, determining fitness level metric includes dividing the determined amount of calories expended by the integrated lactate amount during the activity period.

[0048] In certain embodiments, determining fitness level metric includes dividing the determined amount of calories expended by the lactate level fluctuation information during the activity period.

[0049] In certain embodiments, performing fitness level analysis includes determining a peak lactate level during the activity period, where determining fitness level metric includes dividing the determined amount of calories expended by the determined peak lactate level during the activity period.

[0050] In certain embodiments, the fitness level determination includes outputting a fitness level indicator corresponding to the generated fitness level metric.

[0051] In certain embodiments, the fitness level determination includes monitoring heart rate information during the activity period, and wherein performing the fitness level analysis includes processing the monitored heart rate information.

[0052] In certain embodiments, receiving lactate level fluctuation information from the lactate sensor during the activity period includes positioning an in vivo lactate sensor in fluid contact with bodily fluid under a skin surface, and receiving signals from the lactate sensor corresponding to real time monitored lactate level fluctuation information.

[0053] In certain embodiments, the bodily fluid includes dermal fluid.

[0054] In certain embodiments, the bodily fluid includes interstitial fluid.

[0055] In certain embodiments, the lactate sensor includes a plurality of electrodes including a working electrode comprising an analyte-responsive enzyme bonded to a polymer disposed on the working electrode.

[0056] In certain embodiments, the analyte-responsive enzyme is chemically bonded to the polymer disposed on the working electrode.

[0057] In certain embodiments, the working electrode comprises a mediator bonded to the polymer disposed on the working electrode.

[0058] In certain embodiments, the mediator is crosslinked with the polymer disposed on the working electrode.

[0059] In certain embodiments, the lactate sensor includes a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

[0060] In certain embodiments, determining the amount of calories expended during the activity period includes receiving manually provided information corresponding to the amount of calories expended during the activity period.

[0061] An apparatus for determining a fitness level during an activity period in accordance with one embodiment includes an in vivo lactate sensor in fluid contact with bodily fluid under a skin surface, the lactate sensor configured to generate signals corresponding to monitored lactate level in the bodily fluid, a data input interface configured to receive an amount of calories expended during an activity period, and lactate level fluctuation information from the lactate sensor during the activity period, a fitness monitoring unit operatively coupled to the data input interface, configured to perform a fitness level analysis based on the received amount of calories expended and the lactate level fluctuation information, the fitness monitoring unit further configured to determine a fitness level metric based on performing the fitness level analysis.

[0062] In certain embodiments, the fitness monitoring unit performing fitness level analysis determines an integrated lactate amount during the activity period. [0063] In certain embodiments, the fitness monitoring unit determining the integrated lactate amount determines the area under the curve defined by the lactate level fluctuation information over the activity period.

[0064] In certain embodiments, the fitness monitoring unit determining fitness level metric divides the determined amount of calories expended by the integrated lactate amount during the activity period.

[0065] In certain embodiments, the fitness monitoring unit determining fitness level metric divides the determined amount of calories expended by the lactate level fluctuation information during the activity period.

[0066] In certain embodiments, the fitness monitoring unit performing fitness level analysis determines a peak lactate level during the activity period, where the fitness monitoring unit determining fitness level metric divides the determined amount of calories expended by the determined peak lactate level during the activity period.

[0067] In certain embodiments, the apparatus has a data output interface operatively coupled to the fitness monitoring unit, the data output interface configured to output a fitness level indicator corresponding to the generated fitness level metric.

[0068] In certain embodiments, the apparatus includes a heart rate monitor to monitor heart rate information during the activity period, and wherein the fitness monitoring unit performing the fitness level analysis processes the monitored heart rate information.

[0069] In certain embodiments, the bodily fluid includes dermal fluid.

[0070] In certain embodiments, the bodily fluid includes interstitial fluid.

[0071] In certain embodiments, the lactate sensor includes a plurality of electrodes including a working electrode comprising an analyte-responsive enzyme bonded to a polymer disposed on the working electrode.

[0072] In certain embodiments, the analyte-responsive enzyme is chemically bonded to the polymer disposed on the working electrode.

[0073] In certain embodiments, the working electrode comprises a mediator bonded to the polymer disposed on the working electrode.

[0074] In certain embodiments, the mediator is crosslinked with the polymer disposed on the working electrode. [0075] In certain embodiments, the lactate sensor includes a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

[0076] In certain embodiments, the fitness monitoring unit determining the amount of calories expended during the activity period receives manually provided information corresponding to the amount of calories expended during the activity period.

[0077] In certain embodiments, the fitness monitoring unit includes a user interface of one or more of a mobile telephone, a tablet computing device, a server, a laptop computer, or a wearable physiological condition monitoring device, and a smart watch.

[0078] Various other modifications and alterations in the structure and method of operation of this disclosure will be apparent to those skilled in the art without departing from the scope and spirit of the embodiments of the present disclosure. Although the present disclosure has been described in connection with particular embodiments, it should be understood that the present disclosure as claimed should not be unduly limited to such particular embodiments. It is intended that the following claims define the scope of the present disclosure and that structures and methods within the scope of these claims and their equivalents be covered thereby.

Claims

WHAT IS CLAIMED IS:

1. A method of determining a fitness level during an activity period, comprising: determining an amount of calories expended during an activity period;

receiving lactate level fluctuation information from a lactate sensor during the activity period;

performing a fitness level analysis based on the amount of calories expended and the received lactate level fluctuation information; and

determining a fitness level metric based on performing the fitness level analysis.

2. The method of claim 1, wherein performing the fitness level analysis includes determining an integrated lactate amount during the activity period.

3. The method of claim 2, wherein determining the integrated lactate amount includes determining the area under the curve defined by the lactate level fluctuation information over the activity period.

4. The method of claim 2, wherein determining the fitness level metric includes dividing the determined amount of calories expended by the integrated lactate amount during the activity period.

5. The method of claim 1, wherein determining the fitness level metric includes dividing the determined amount of calories expended by the lactate level fluctuation information during the activity period.

6. The method of claim 1, wherein performing the fitness level analysis includes determining a peak lactate level during the activity period.

7. The method of claim 6, wherein determining the fitness level metric includes dividing the determined amount of calories expended by the determined peak lactate level during the activity period.

8. The method of claim 1, further including outputting a fitness level indicator corresponding to the determined fitness level metric.

9. The method of claim 1, further including monitoring a heart rate information during the activity period, and wherein performing the fitness level analysis includes processing the monitored heart rate information.

10. The method of claim 1, wherein receiving lactate level fluctuation information from the lactate sensor during the activity period includes positioning an in vivo lactate sensor in fluid contact with bodily fluid under a skin surface, and receiving signals from the lactate sensor corresponding to real time monitored lactate level fluctuation information.

11. The method of claim 10, wherein the bodily fluid includes dermal fluid.

12. The method of claim 10, wherein the bodily fluid includes interstitial fluid.

13. The method of claim 1, wherein the lactate sensor includes a plurality of electrodes including a working electrode comprising an analyte-responsive enzyme bonded to a polymer disposed on the working electrode.

14. The method of claim 13, wherein the analyte-responsive enzyme is chemically bonded to the polymer disposed on the working electrode.

15. The method of claim 13, wherein the working electrode comprises a mediator bonded to the polymer disposed on the working electrode.

16. The method of claim 15, wherein the mediator is crosslinked with the polymer disposed on the working electrode.

17. The method of claim 1, wherein the lactate sensor includes a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

18. The method of claim 1, wherein determining the amount of calories expended during the activity period includes receiving manually provided information

corresponding to the amount of calories expended during the activity period.

19. An apparatus for determining a fitness level during an activity period, comprising: an in vivo lactate sensor in fluid contact with bodily fluid under a skin surface, the lactate sensor configured to generate signals corresponding to monitored lactate level in the bodily fluid;

a data input interface configured to receive an amount of calories expended during an activity period, and lactate level fluctuation information from the lactate sensor during the activity period; and

a fitness monitoring unit operatively coupled to the data input interface, configured to perform a fitness level analysis based on the received amount of calories expended and the lactate level fluctuation information, the fitness monitoring unit further configured to determine a fitness level metric based on performing the fitness level analysis.

20. The apparatus of claim 19, wherein the fitness monitoring unit performing the fitness level analysis determines an integrated lactate amount during the activity period.

21. The apparatus of claim 20, wherein the fitness monitoring unit determining the integrated lactate amount determines the area under the curve defined by the lactate level fluctuation information over the activity period.

22. The apparatus of claim 20, wherein the fitness monitoring unit determining the fitness level metric divides the received amount of calories expended by the integrated lactate amount during the activity period.

23. The apparatus of claim 19, wherein the fitness monitoring unit determining the fitness level metric divides the determined amount of calories expended by the lactate level fluctuation information during the activity period.

24. The apparatus of claim 19, wherein the fitness monitoring unit performing the fitness level analysis determines a peak lactate level during the activity period.

25. The apparatus of claim 24, wherein the fitness monitoring unit determining the fitness level metric divides the received amount of calories expended by the determined peak lactate level during the activity period.

26. The apparatus of claim 19, further including a data output interface operatively coupled to the fitness monitoring unit, the data output interface configured to output a fitness level indicator corresponding to the determined fitness level metric.

27. The apparatus of claim 19, further including a heart rate monitor to monitor a heart rate information during the activity period, and wherein the fitness monitoring unit performing the fitness level analysis processes the monitored heart rate information.

28. The apparatus of claim 19, wherein the bodily fluid includes dermal fluid.

29. The apparatus of claim 19, wherein the bodily fluid includes interstitial fluid.

30. The apparatus of claim 19, wherein the lactate sensor includes a plurality of electrodes including a working electrode comprising an analyte-responsive enzyme bonded to a polymer disposed on the working electrode.

31. The apparatus of claim 30, wherein the analyte-responsive enzyme is chemically bonded to the polymer disposed on the working electrode.

32. The apparatus of claim 30, wherein the working electrode comprises a mediator bonded to the polymer disposed on the working electrode.

33. The apparatus of claim 32, wherein the mediator is crosslinked with the polymer disposed on the working electrode.

34. The apparatus of claim 19, wherein the lactate sensor includes a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

35. The apparatus of claim 19, wherein the fitness monitoring unit performing fitness level analysis based on the received amount of calories expended during the activity period receives manually provided information corresponding to the amount of calories expended during the activity period.

36. The apparatus of claim 19, wherein the fitness monitoring unit includes a user interface of one or more of a mobile telephone, a tablet computing device, a server, a laptop computer, or a wearable physiological condition monitoring device, and a smart watch.