System and method for reliably coordinating musculoskeletal and cardiovascular hemodynamics

• US 8,961,185 B2
• Filed: 08/17/2012
• Issued: 02/24/2015
• Est. Priority Date: 08/19/2011
• Status: Active Grant

• Current Assignee: Pulson, Inc.
• Original Assignee: Pulson, Inc.
• Inventors: Bleich, Jeffery Lee, Mannheimer, Paul David, Michels, Jeffrey Lawrence, Anker, Marc David
• Primary Examiner(s): Musselman, Timothy A
• Application Number:
  US13/589,073
• Publication Number:
  US 20130171599A1
• Time in Patent Office: 921 Days
• Field of Search: 434/247, 434322-365, 482 1- 9
• US Class Current: 434/247
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/486 Bio-feedback A61B5/375 takes precedence
• CPC Class Codes: A61B 5/744 Displaying an avatar, e.g. an animated cartoon character
• CPC Class Codes: A61H 1/0255 Both knee and hip of a patient, e.g. in supine or sitting position, the feet being moved together in a plane substantially parallel to the body-symmetrical plane A61H1/0214 takes precedence
• CPC Class Codes: A61H 1/0274 for the upper limbs
• CPC Class Codes: A61H 2201/1633 Seat A61H2201/0149 takes precedence
• CPC Class Codes: A61H 2201/1642 Holding means therefor
• CPC Class Codes: A61H 2201/5015 using specific interfaces or standards, e.g. USB, serial, parallel
• CPC Class Codes: A61H 2201/5064 Position sensors
• CPC Class Codes: A61H 2201/5071 Pressure sensors
• CPC Class Codes: A61H 2201/5084 Acceleration sensors
• CPC Class Codes: A61H 2201/5092 Optical sensor
• CPC Class Codes: A61H 2201/5097 wireless
• CPC Class Codes: A61H 2230/045 used as a control parameter for the apparatus
• CPC Class Codes: A61H 2230/065 used as a control parameter for the apparatus
• CPC Class Codes: A61H 2230/208 : used as a control parameter for the apparatus
• CPC Class Codes: A61H 2230/305 : used as a control parameter for the apparatus A61H2230/045 takes precedence
• CPC Class Codes: A61H 2230/42 : Rate
• CPC Class Codes: A61H 2230/50 : Temperature
• CPC Class Codes: A61H 2230/60 : Muscle strain, i.e. measured on the user, e.g. Electromyography [EMG]
• CPC Class Codes: A61H 2230/805 : used as a control parameter for the apparatus
• CPC Class Codes: A61H 3/00 : Appliances for aiding patients or disabled persons to walk about apparatus for helping babies to walk A47D13/04 ; applying electrical currents by contact electrodes for stimulating motor muscles, e.g. walking assistance A61N1/36003
• CPC Class Codes: A63B 15/00 : Clubs for gymnastics or the like , e.g. for swinging exercises
• CPC Class Codes: A63B 2024/0093 : the load of the exercise apparatus being controlled by performance parameters, e.g. distance or speed
• CPC Class Codes: A63B 2024/0096 : using performance related parameters for controlling electronic or video games or avatars
• CPC Class Codes: A63B 2071/0625 : Emitting sound, noise or music
• CPC Class Codes: A63B 2071/0655 : Tactile feedback
• CPC Class Codes: A63B 2071/0663 : worn on the wrist, e.g. wrist bands
• CPC Class Codes: A63B 21/0023 : for isometric exercising, i.e. substantial force variation without substantial muscle motion
• CPC Class Codes: A63B 21/06 : User-manipulated weights
• CPC Class Codes: A63B 22/0023 : the inclination of the main axis of the movement path being adjustable, e.g. the inclination of an endless band
• CPC Class Codes: A63B 22/0056 : the pivoting movement being in a vertical plane, e.g. steppers with a horizontal axis platforms for rocking motion about a horizontal axis A63B22/16
• CPC Class Codes: A63B 22/0076 : Rowing machines for conditioning the cardio-vascular system seats moving during exercise A63B22/0087; training appliances for rowing or sculling on boats A63B69/06
• CPC Class Codes: A63B 22/0235 : driven by a motor
• CPC Class Codes: A63B 22/0605 : performing a circular movement, e.g. ergometers
• CPC Class Codes: A63B 22/0664 : performing an elliptic movement
• CPC Class Codes: A63B 2220/10 : Positions
• CPC Class Codes: A63B 2220/17 : Counting, e.g. counting periodical movements, revolutions or cycles, or including further data processing to determine distances or speed
• CPC Class Codes: A63B 2220/40 : Acceleration
• CPC Class Codes: A63B 2220/56 : Pressure
• CPC Class Codes: A63B 2220/805 : Optical or opto-electronic sensors
• CPC Class Codes: A63B 2220/806 : Video cameras
• CPC Class Codes: A63B 2220/833 : Sensors arranged on the exercise apparatus or sports implement
• CPC Class Codes: A63B 2220/836 : Sensors arranged on the body of the user
• CPC Class Codes: A63B 2220/89 : Field sensors, e.g. radar systems
• CPC Class Codes: A63B 2225/50 : Wireless data transmission, e.g. by radio transmitters or telemetry
• CPC Class Codes: A63B 2225/54 : Transponders, e.g. RFID
• CPC Class Codes: A63B 2230/045 : used as a control parameter for the apparatus
• CPC Class Codes: A63B 2230/062 : used as a control parameter for the apparatus
• CPC Class Codes: A63B 2230/207 : P-O2, i.e. partial O2 value
• CPC Class Codes: A63B 2230/425 : used as a control parameter for the apparatus
• CPC Class Codes: A63B 2230/50 : temperature
• CPC Class Codes: A63B 2230/60 : muscle strain, i.e. measured on the user
• CPC Class Codes: A63B 2230/75 : calorie expenditure
• CPC Class Codes: A63B 2244/20 : Swimming
• CPC Class Codes: A63B 23/1218 : Chinning, pull-up, i.e. concentric movement
• CPC Class Codes: A63B 23/1236 : Push-ups in horizontal position, i.e. eccentric movement
• CPC Class Codes: A63B 24/0062 : Monitoring athletic performances, e.g. for determining the work of a user on an exercise apparatus, the completed jogging or cycling distance
• CPC Class Codes: A63B 24/0075 : Means for generating exercise programs or schemes, e.g. computerized virtual trainer, e.g. using expert databases
• CPC Class Codes: A63B 24/0087 : Electric or electronic controls for exercising apparatus of groups A63B21/00 - A63B23/00, e.g. controlling load
• CPC Class Codes: A63B 69/0028 : for running, jogging or speed-walking movable endless bands A63B22/02
• CPC Class Codes: A63B 71/0686 : Timers, rhythm indicators or pacing apparatus using electric or electronic means
• CPC Class Codes: G09B 19/00 : Teaching not covered by other main groups of this subclass teaching or practice apparatus for gun-aiming or gun-laying F41G3/26
• CPC Class Codes: G09B 19/0038 : Sports
• CPC Class Codes: G16H 20/30 : relating to physical therapies or activities, e.g. physiotherapy, acupressure or exercising
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture

Abstract

Systems and methods are disclosed to enable a user to favorably coordinate the timing of musculoskeletal movement and skeletal muscle contraction and relaxation with the cardiac pumping cycle in order to improve perfusion of cardiac and peripheral skeletal muscle and other tissues, increase physiological efficiency, decrease myocardial stress, and enhance individual performance, health and safety during rhythmic physical activity. Additionally, systems and methods are disclosed to enable a user to avoid inadvertent unfavorable coordination of musculoskeletal movement and skeletal muscle contractions and relaxation cycles with the cardiac pumping cycle during physical activity.

Claims

1. A method for detecting a cardiovascular cycle of a user, generating data corresponding to the cardiovascular cycle and using the data to coordinate a rhythmic musculoskeletal activity of the user with the cardiovascular cycle of the user, comprising:

detecting instances of a selected aspect of the cardiovascular cycle of the user using a first detector, said selected aspect repeating at a heart rate of the user;

specifying a target timing location in the cardiovascular cycle to a subsystem based on the data generated from a plurality of said instances detected by the first detector;

recurrently providing a prompt from a prompt device to the user at a prompt rate to thereby provide a timing indication for performance of the rhythmic musculoskeletal activity, the prompt being provided such that the heart rate is substantially an integer multiple of the prompt rate; and

adaptively adjusting timing of the prompt using a processor that receives the target timing location and adaptively adjusts the timing of the prompt automatically so that the prompt is provided by the prompt device to the user substantially at the target timing location in the cardiovascular cycle in response to detected change in the timing of the cardiovascular cycle.

2. The method of claim 1, wherein said adaptively adjusting maintains either a fixed percentage of an R-wave-to-R-wave time interval of the user or said prompt being located at a fixed event in the cardiovascular cycle of the user.

3. The method of claim 1, wherein said adjusting comprises a user-selected, time-based offset from said aspect of the user'"'"'s cardiovascular cycle.

4. The method of claim 1, wherein said adjusting comprises an offset from said aspect of the user'"'"'s cardiovascular cycle automatically determined based on a physiological attribute of the user.

5. The method of claim 4, wherein the physiological attribute is selected, using the processor, from the group consisting of:

user age;

user heart rate;

user blood pressure;

user'"'"'s maximum heart rate; and

, user target heart rate.

6. The method of claim 1, wherein said adjusting comprises an offset from said aspect of the user'"'"'s cardiovascular cycle automatically determined based on a type of rhythmic musculoskeletal activity the user is to perform.

7. The method of claim 1, further comprising:

detecting a selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity using a second detector that repeats at a cadence of the user; and

wherein based on said detected components of the user'"'"'s cardiovascular cycle and the user'"'"'s rhythmic musculoskeletal activity, further adjusting said prompt using the processor such that said prompt is provided to guide timing of the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity to occur at a targeted timing relative to the selected recurrent aspect of the user'"'"'s cardiovascular cycle.

8. The method of claim 7, further comprising:

determining a desired offset between the provision of said prompt and the selected recurrent component the user'"'"'s rhythmic musculoskeletal activity using the processor;

determining an actual offset between the provision of said prompt and the selected recurrent component the user'"'"'s rhythmic musculoskeletal activity using the processor; and

in response to said determined actual offset, further adjusting provision of the prompt to permit said component of the user'"'"'s rhythmic musculoskeletal activity to occur at a desired point in the user'"'"'s cardiovascular cycle using the processor.

9. The method of claim 7, further comprising:

determining an offset between the selected recurrent component the user'"'"'s rhythmic musculoskeletal activity and the target timing location in the cardiovascular cycle using the processor; and

in response to said determined offset, further adjusting provision of the prompt using the processor to permit said component of the user'"'"'s rhythmic musculoskeletal activity to occur at a desired point in the user'"'"'s cardiovascular cycle.

10. The method of claim 1, wherein said integer multiple is determined automatically using the processor based on at least one of the group consisting of:

the type of rhythmic musculoskeletal activity the user is to perform;

a ratio of the user'"'"'s heart rate to a target musculoskeletal activity cadence; and

a ratio of the user'"'"'s heart rate to an indication of their actual musculoskeletal activity cadence.

11. The method of claim 1, wherein said prompt is at least one of the group consisting of:

an audio prompt;

a visual prompt; and

, a tactile prompt.

12. A method for detecting a cardiovascular cycle of a user, generating data corresponding to the cardiovascular cycle and using the data to coordinate a rhythmic musculoskeletal activity of the user with the cardiovascular cycle of the user, comprising:

providing a recurrent prompt to the user from a prompt device to thereby provide a timing indication to the user for performance of the rhythmic musculoskeletal activity;

detecting a selected recurrent aspect of the user'"'"'s cardiovascular cycle that repeats at a heart rate of the user using a first detector;

detecting a selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity that repeats at a cadence of the user using a second detector; and

wherein based on the data generated from said detected aspect of the user'"'"'s cardiovascular cycle and the detected selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity, adapting provision of the prompt using a processor that receives the target timing location and adaptively adjusts the timing of the prompt automatically such that said prompt is provided so as to coordinate timing of the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity to occur with a targeted timing relationship relative to the timing of the selected recurrent aspect of the user'"'"'s cardiovascular cycle.

13. The method of claim 12, wherein said prompt is provided substantially at a desired point in the user'"'"'s cardiovascular cycle.

14. The method of claim 12, wherein said selected recurrent aspect of the user'"'"'s cardiovascular cycle is represented by a first signal from the first detector and said recurrent component of the user'"'"'s rhythmic musculoskeletal activity is represented by a second signal from the second detector, and said adapting of the provision of the prompt comprises comparing timing of the first and second signals relative to one another using the processor.

15. The method of claim 14, wherein:

the recurrent prompt is provided at a prompt rate using the prompt device;

the cardiovascular cycle is a full cycle of the user'"'"'s heart pumping function;

the heart rate of the user is an integer multiple of the prompt rate; and

the prompt is adaptively provided at an offset from an aspect of the detected cardiovascular cycle of the user.

16. The method of claim 15, wherein said offset is selected from the group consisting of:

a time-based offset; and

, a percentage of an interval-based offset.

17. The method of claim 14, wherein said recurrent first signal is selected from the group consisting of:

an electro-cardio-graphic R-wave of the user, an electro-cardio-graphic T-wave of the user;

an end of the electro-cardio-graphic T-wave of the user;

a feature of a photoplethysmogram (PPG) waveform of the user;

a peak of a cardiovascular systolic pressure of the user;

a nadir of a diastolic cardiovascular pressure of the user; and

, a transition point in a cardiovascular pressure of the user.

18. The method of claim 17, wherein said first signal comprises the user'"'"'s electro-cardio-graphic R-wave, and further wherein said offset is a time-based offset, τ

, such that the prompt is provided at time τ

after detection of the R-wave.

19. The method of claim 18, wherein τ

is determined as a function of at least one value from the group consisting of;

a target heart rate of the user;

beat-to-beat heart rate of the user;

average heart rate of the user;

pulse-periods of the user;

average pulse-period of the user; and

, a type of user activity producing the recurrent component the user'"'"'s rhythmic musculoskeletal activity.

20. The method of claim 19, wherein τ

is determined as a function of the target heart rate, and further comprising receiving a user input representing the target heart rate using at least one of the first detector and a user interface.

21. The method of claim 12, wherein the second detector includes the use of at least one of an accelerometer, an EMG sensor, a pressure sensor, a gyroscope, and an electromechanical sensor.

22. The method of claim 12, wherein said prompt is at least one of the group consisting of:

an audio prompt;

a visual prompt; and

, a tactile prompt.

23. The method of claim 12, further comprising:

determining a desired offset between the provision of said prompt and the selected recurrent component the user'"'"'s rhythmic musculoskeletal activity using the processor;

determining an actual offset between the provision of said prompt and the selected recurrent component the user'"'"'s rhythmic musculoskeletal activity using the processor; and

in response to said determined actual offset, further adapting provision of the prompt using the processor.

24. The method of claim 23, wherein said actual offset is determined as a time-averaged offset between the provision of said prompt and the selected recurrent component the user'"'"'s rhythmic musculoskeletal activity.

25. The method claim 23, further comprising, in response to said determined actual offset, automatically adjusting conditions of the rhythmic musculoskeletal activity to reduce said actual offset using the processor.

26. The method of claim 25, wherein said automatically adjusting comprises providing a signal from the processor to an electro-mechanical exercise apparatus so as to adjust operating conditions of said electro-mechanical exercise apparatus.

27. The method of claim 12, further comprising:

determining an actual offset between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the target timing location in the cardiovascular cycle using the processor; and

in response to said determined actual offset, further adjusting provision of the prompt using the processor to permit said component of the user'"'"'s rhythmic musculoskeletal activity to occur at a desired point in the user'"'"'s cardiovascular cycle.

28. The method of claim 27, wherein said actual offset is determined using the processor as a time-averaged offset between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the target timing location in the cardiovascular cycle.

29. The method claim 27, further comprising, in response to said determined actual offset, automatically adjusting conditions of the rhythmic musculoskeletal activity to reduce said actual offset using the processor.

30. The method of claim 29, wherein said automatically adjusting comprises providing a signal from the processor to an electro-mechanical exercise apparatus so as to adjust operating conditions of said electro-mechanical exercise apparatus.

31. The method of claim 12, wherein said prompt is provided substantially at a variable desired point in the user'"'"'s cardiovascular cycle.

32. The method of claim 31, wherein the desired point in the user'"'"'s cardiovascular cycle at which the prompt is adaptively provided varies as a function of time that the user performs the rhythmic musculoskeletal activity.

33. The method of claim 31, wherein the desired point in the user'"'"'s cardiovascular cycle at which the prompt is adaptively provided varies as a function of the user'"'"'s heart rate while the user performs the rhythmic musculoskeletal activity.

34. The method of claim 31, wherein the desired point in the user'"'"'s cardiovascular cycle at which the prompt is adaptively provided varies as a function of the user'"'"'s blood pressure while the user performs the rhythmic musculoskeletal activity.

35. The method of claim 12, further comprising:

using the processor to selectively modify said prompt based on at least one condition selected from the group consisting of;

heart rate of the user while performing said rhythmic musculoskeletal activity;

cadence of the user while performing said rhythmic musculoskeletal activity; and

, relative timing relationship between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the selected recurrent aspect of the user'"'"'s cardiovascular cycle.

36. The method of claim 35, wherein said prompt is further selectively modified when a relative timing relationship between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the selected recurrent aspect of the user'"'"'s cardiovascular cycle represents an undesirable condition.

37. A system for detecting a cardiovascular cycle of a user, generating data corresponding to the cardiovascular cycle and using the data to coordinate a rhythmic musculoskeletal activity of the user with the cardiovascular cycle of the user, comprising:

a first detector for detecting instances of a selected aspect of the cardiovascular cycle of the user, said selected aspect repeating at a heart rate of the user;

a subsystem for specifying a target timing location in the cardiovascular cycle of the user based on the data generated from a plurality of said instances detected by the first detector;

a prompt device for recurrently providing a prompt to the user at a prompt rate to thereby provide a timing indication for performance of the rhythmic musculoskeletal activity, the prompt being provided such that the heart rate is substantially an integer multiple of the prompt rate; and

a processor that receives target timing location and adaptively adjusting timing of the prompt automatically so that the prompt is provided by the prompt device to the user substantially at the target timing location in the cardiovascular cycle in response to a detected change in the timing of the cardiovascular cycle.

38. The system of claim 37, wherein said processor is configured to adaptively adjust said timing to maintain either a fixed percentage of an R-wave to-R-wave time interval of the user or to located said prompt at a fixed event in the cardiovascular cycle of the user.

39. The system of claim 37, further comprising an interface configured to permit user-selected, time-based adjustment of said offset.

40. The system of claim 37, further comprising a user interface for entering or selecting, or a sensor for sensing a physiological attribute of the user, and further wherein said processor is configured such that said adjusting comprises an offset from said aspect of the user'"'"'s cardiovascular cycle automatically determined based on said physiological attribute of the user.

41. The system of claim 40, wherein said physiological attribute is selected from the group consisting of:

user age;

user weight;

user blood pressure;

user heart rate;

user'"'"'s maximum heart rate; and

, user target heart rate.

42. The system of claim 37, wherein said processor is configured such that said adjusting comprises an offset from said aspect of the user'"'"'s cardiovascular cycle automatically determined based on a type of rhythmic musculoskeletal activity the user is to perform.

43. The system of claim 37, further comprising:

a second detector for detecting a selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity that repeats at a cadence of the user; and

said processor is configured such that, based on said detected components of the user'"'"'s cardiovascular cycle and the user'"'"'s rhythmic musculoskeletal activity, said processor further adjusts said prompt such that said prompt is provided to guide timing of the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity to occur substantially at the targeted timing relative to the selected recurrent aspect of the user'"'"'s cardiovascular cycle.

44. The system of claim 43, further comprising:

said processor configured for determining a desired offset between the provision of said prompt and the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity;

said processor further configured for determining an actual offset between the provision of said prompt and the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity; and

said processor further configured for, in response to said determined actual offset, further adjusting provision of the prompt to permit said component of the user'"'"'s rhythmic musculoskeletal activity to occur at a desired point in the user'"'"'s cardiovascular cycle.

45. The system of claim 43, further comprising:

said processor further configured for determining an offset between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the target timing location in the cardiovascular cycle; and

said processor further configured for, in response to said determined offset, further adjusting provision of the prompt to permit said component of the user'"'"'s rhythmic musculoskeletal activity to occur at a desired point in the user'"'"'s cardiovascular cycle.

46. The system of claim 37, wherein said processor is further configured for automatically determining said integer multiple based on at least one of the group consisting of:

the type of rhythmic musculoskeletal activity the user is to perform;

a ratio of the user'"'"'s heart rate to a target musculoskeletal activity cadence; and

a ratio of the user'"'"'s heart rate to an indication of their actual musculoskeletal activity cadence.

47. The system of claim 37, wherein said prompt device is configured to provide said prompt of a type selected from the group consisting of:

an audio prompt;

a visual prompt; and

, a tactile prompt.

48. A system for detecting a cardiovascular cycle of a user, generating data corresponding to the cardiovascular cycle and using the data to coordinate a rhythmic musculoskeletal activity of the user with the rhythmic cardiovascular cycle of the user, comprising:

a prompt device for providing a recurrent prompt to the user to thereby provide a timing indication for performance of the rhythmic musculoskeletal activity;

a first detector for detecting a selected recurrent aspect of the user'"'"'s cardiovascular cycle that repeats at a heart rate of the user;

a second detector for detecting a selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity that repeats at a cadence of the user; and

a processor, responsive to the data generated from said detection of said selected recurrent aspect of the cardiovascular cycle of the user and the detection of said selected recurrent component of the rhythmic musculoskeletal activity of the user, for automatically and adaptively providing the prompt so as to coordinate timing of the selected recurrent component of the rhythmic musculoskeletal activity of the user to occur with a targeted timing relationship relative to the timing of the selected recurrent aspect of the cardiovascular cycle of the user.

49. The system of claim 48, wherein said processor is configured to provide said prompt substantially at a desired point in the user'"'"'s cardiovascular cycle.

50. The system of claim 48, wherein said first detector represents said selected recurrent aspect of the user'"'"'s cardiovascular cycle by a first detected signal and said second detector represents said recurrent component of the user'"'"'s rhythmic musculoskeletal activity by a second detected signal, and said processor is configured to adapt the provision of the prompt by comparing timing of the first and second detected signals relative to one another.

51. The system of claim 50, wherein:

the prompt device provides the recurrent prompt at a prompt rate;

the cardiovascular cycle is a full cycle of the user'"'"'s heart pumping function;

the detected heart rate of the user is an integer multiple of the prompt rate; and

said processor is configured to provide the prompt at an offset from the aspect of the cardiovascular cycle of the user.

52. The system of claim 51, wherein said processor is configured to provide the prompt at an offset selected from the group consisting of:

a time-based offset; and

, a percentage of an interval-based offset.

53. The system of claim 50, wherein said recurrent first detected signal is selected from the group consisting of:

an electro-cardio-graphic R-wave of the user, an electro-cardio-graphic T-wave of the user;

an end of an electro-cardio-graphic T-wave of the user;

a feature of a photoplethysmogram (PPG) waveform of the user;

a peak of a cardiovascular systolic pressure of the user;

a nadir of a diastolic cardiovascular pressure of the user; and

, a transition point in a cardiovascular pressure of the user.

54. The system of claim 53, wherein said recurrent first detected signal comprises the user'"'"'s electro-cardio-graphic R-wave, and further wherein said offset is a time-based offset, τ

, said prompt device providing said prompt at time τ

after detection by said first detector of the R-wave.

55. The system of claim 54, wherein said processor is configured to determine τ

as a function of at least one value from the group consisting of;

a target heart rate of the user;

beat-to-beat heart rate of the user;

average heart rate of the user;

pulse-periods of the user;

average pulse-period of the user; and

, a type of user activity producing the recurrent component the user'"'"'s rhythmic musculoskeletal activity.

56. The system of claim 55, wherein τ

is determined as a function of the target heart rate, and further comprising an interface for receiving a user input representing the target heart rate.

57. The system of claim 48, further comprising, and configured for measurement of the recurrent component of the user'"'"'s rhythmic musculoskeletal activity, at least one of an accelerometer, an EMG sensor, a pressure sensor, a gyroscope, and an electromechanical sensor.

58. The system of claim 48, wherein said prompt device is configured to provide said prompt as at least one of the group consisting of:

an audio prompt;

a visual prompt; and

, a tactile prompt.

59. The system of claim 48, further comprising:

said processor configured for determining a desired offset between the provision of said prompt and the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity;

said processor configured for determining an actual offset between the provision of said prompt and the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity; and

said processor configured for, in response to said determined actual offset, further adapting provision of the prompt.

60. The system of claim 59, wherein said processor is configured for determining said actual offset as a time-averaged offset between the provision of said prompt and the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity.

61. The system claim 59, wherein said processor is configured for automatically adjusting, in response to said determined actual offset, conditions of the rhythmic musculoskeletal activity to reduce said actual offset.

62. The system of claim 61, further comprising an electro-mechanical exercise apparatus communicatively coupled to said processor such that said automatically adjusting comprises said processor providing a signal to said electro-mechanical exercise apparatus so as to adjust operating conditions of said electro-mechanical exercise apparatus.

63. The system of claim 48, further comprising:

a third detector for determining an actual offset between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the target timing location in the cardiovascular cycle; and

said processor configured such that, in response to said determined actual offset, provision of the prompt is further adjusted to permit said component of the user'"'"'s rhythmic musculoskeletal activity to occur at a desired point in the user'"'"'s cardiovascular cycle.

64. The system of claim 63, wherein said processor is configured to determine said actual offset as a time-averaged offset between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the target timing location in the cardiovascular cycle.

65. The system claim 63, wherein said processor is configured to, in response to said determined actual offset, automatically adjust conditions of the rhythmic musculoskeletal activity to reduce said actual offset.

66. The system of claim 65, further comprising an electro-mechanical exercise apparatus communicatively coupled to said processor such that said automatically adjusting comprises said processor providing a signal to said electro-mechanical exercise apparatus so as to adjust operating conditions of said electro-mechanical exercise apparatus.

67. The system of claim 48, wherein said processor is configured to provide said prompt substantially at a variable point in the user'"'"'s cardiovascular cycle.

68. The system of claim 67, wherein said processor is configured to operate with said desired point varying as a function of time that the user performs the rhythmic musculoskeletal activity.

69. The system of claim 67, wherein said processor is configured to operate with said desired point varying as a function of the user'"'"'s heart rate while the user performs the rhythmic musculoskeletal activity.

70. The system of claim 67, wherein said processor is configured to operate with said desired point varying as a function of the user'"'"'s blood pressure while the user performs the rhythmic musculoskeletal activity.

71. The system of claim 48, further comprising:

said processor being configured to selectively modify said prompt based on at least one condition selected from the group consisting of;

heart rate of the user while performing said rhythmic musculoskeletal activity;

cadence of the user while performing said rhythmic musculoskeletal activity; and

, relative timing relationship between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the selected recurrent aspect of the user'"'"'s cardiovascular cycle.

72. The system of claim 71, wherein said processor is configured to selectively modify said prompt when a relative timing relationship, determined by said processor, between the selected recurrent component of the user'"'"'s rhythmic musculoskeletal activity and the selected recurrent aspect of the user'"'"'s cardiovascular cycle represents an undesirable condition.