Automatic device for optimized muscular stimulation

Abstract

The invention relates to an automatic device for optimized muscular stimulation, the stimulation providing periodical contractions with constant frequency of one or more muscles of a user, the device comprising a central electronic unit (1), connected to a memory unit (2), to one or more muscular electrical activity detectors (4), each one applied on a corresponding muscle of the user to be subjected to stimulation, and to muscular stimulation means (5) actuated by the central unit (1), the central unit (1) managing and controlling the automatic device, processing the data coming from the detectors (4) in such a way to determine, within a range included between a lower limit frequency and an upper limit frequency, an optimum frequency of the periodical contractions in correspondence of which the sum of the amplitude of the signals provided by the detectors (4) from the corresponding muscles of the user as a response to the stimulation is the maximum one, the central unit (1) setting the muscular stimulation means (5) in such a way to produce periodical contractions of the muscle to be stimulated at the determined optimum frequency.

Description

FIELD OF THE INVENTION

[0001] The present invention relates to an automatic device for optimized mechanical muscular stimulation andlor stressing.

BACKGROUND

[0002] More specifically, the invention concerns a device of the above kind, the stimulation of which, preferably mechanically produced, provides constant frequency periodical contractions of a muscle of a user, providing the preliminary detection of the frequencies of the periodical contractions corresponding to the best electro-myographycal response for the muscle to be stimulated, and a following stimulation of the same muscle at the optimum frequency sensed, the device being highly reliable and efficient.

[0003] It is known that when a muscle is stimulated by application of mechanical vibrations, it contracts in a reflex way very similarly to what happens when the muscle is operated by voluntary contractions, e.g. during the execution of physical works.

[0004] Particularly, varying the frequency of the mechanical vibrations, it is possible to make selectively working fast or slow muscular fibers.

[0005] Recently, many mechanical devices for the muscular stimulation have been developed, such as a board, for the leg muscles, or a vibrator, for the arm muscles.

[0006] Said devices are useful for training of agonistic level athletes, since they allow to obtain the same results of the standard physical exercises within the gymnasium in a shorter time, to obtain a good muscular tone by few application minutes at home, and for physical therapy uses aimed to the maintenance of the muscular tone or to the functional recover of the muscles, for example during or after immobilization periods due to fractures or surgical intervention.

[0007] However, present mechanical muscular stimulation devices have some drawbacks.

[0008] A main drawback is represented by the fact that the mechanical vibration frequency, that can be manually set, is not optimized either for the specific fibers of a determined muscle of the specific user and for the whole body.

[0009] In fact, in accordance with the invention, it has been found that specific fibers of any muscle of any single user have a variable response to micro-vibrations by varying the frequency of the applied vibration. Particularly, a frequency range can be determined, which can be defined “activity range”, within which specific fibers of the particular muscle respond to the stimulations and, within said range, there can be determined an optimum mechanical frequency in correspondence of which said response is a maximum. If a static applied frequency is different with respect to the optimum one, the work of the interested muscle is not efficient for toning and, muscular work is completely null. In some cases, the wrong vibration frequency could even produce harmful results.

[0010] Similar drawbacks are present in electrical muscle stimulation devices, the frequency of the electrical signal of which, applied to the specific muscle, is not optimized.

[0011] In this situation, it is suggested the solution according to the present invention, allowing to solve all the above mentioned drawbacks.

SUMMARY OF THE INVENTION

[0012] An object of the present invention is that of providing a preferably mechanical device, which is reliable, efficient and simple to be used, for the muscular stimulation, able to determine in an automatic way the optimum periodic stimulated contraction frequency for which the specific fibers of the particular interested muscle have the maximum, not only muscular, but also generally speaking biological, response.

[0013] Still an object of the present invention is that of providing such a device for the muscular electro-stimulation, able to automatically determine the optimum frequency of the electronic signal to be applied at the particular interested muscle in such a way to stimulate periodic contractions with an optimum frequency.

[0014] It is therefore specific object of the present invention an automatic device for optimized muscular stimulation, the stimulation providing periodical contractions with constant frequency of one or more muscles of a user, the device comprising a central electronic unit, connected to a memory unit, to one or more muscular electrical activity detectors, each one applied on a corresponding muscle of the user to be subjected to stimulation, and to muscular stimulation means actuated by the central unit, the central unit managing and controlling the automatic device, processing the data coming from the detectors in such a way to determine, within a range included between a lower limit frequency and an upper limit frequency, an optimum frequency of the periodical contractions in correspondence of which the sum of the amplitude of the signals provided by the detectors from the corresponding muscles of the user as a response to the stimulation is the maximum one, the central unit setting the muscular stimulation means in such a way to produce periodical contractions of the muscle to be stimulated at the determined optimum frequency.

[0015] Preferably, according to the invention, the lower limit frequency is 1 Hz and/or the upper limit frequency is 1000 Hz.

[0016] Still preferably, according to the invention, muscular stimulation means are mechanical means.

[0017] Always according to the invention, the mechanical means can provide a support structure on which a jumpy board is placed, on which the user is placed, comprising a metallic plate at which at least engine is coupled having an eccentric mass, able to produce the vibration of the plate, piloted by an electronic device comprising an inverter connected to a potentiometer adjusting the vibration frequency, the central unit setting said vibration frequency.

[0018] Furthermore according to the invention, the mechanical means can provide a support structure on which a tilting board is placed.

[0019] Still according to the invention, the muscular stimulation means can be electrical means.

[0020] Further, according to the invention, the detector can comprise medical electrodes, amplified in situ, an insulation amplifier and a signal converter providing at the outlet a digital signal read by the central unit.

[0021] According to the invention, each one of said one or more detectors can comprise medical electrodes, amplified in situ, an insulation amplifier and a signal converter providing at the outlet a digital signal read by the central unit.

[0022] Furthermore, according to the invention, the central unit can follow a determination method of the optimum frequency comprising the phases of:

[0023] application of said one or more detectors to the corresponding muscles to be stimulated;

[0024] repetition for N times, preferably eight times, of a data acquisition phase during which the central unit actuates the stimulation means in such a way to produce periodical contractions of the muscle with a constant frequency for a &Dgr;t, preferably between 5 and 10 seconds, with a progressively growing frequency, from a repetition to the following one and included between the lower limit frequency and the upper limit frequency;

[0025] processing, for each repetition, the average of the amplitude of signals coming from the detectors and memorizing the same within the memory unit along with the value of the corresponding frequency; and

[0026] determination of the maximum sum of the average of the amplitude of signals detected by said detectors, wherein the central unit determines, between those memorized, the sum of the averages at the same frequency having the maximum value, individuating the optimum frequency.

[0027] Still according to the invention, consecutive repetition frequencies can have a constant difference.

[0028] Furthermore, according to the invention, the consecutive repetition frequencies can have a variable difference and increasing as a function of the absolute value of the frequency of the preceding repetition.

[0029] Still according to the invention, the central unit can perform a determination method of the optimum frequency, comprising the phases of:

[0030] application of said one or more detectors to the corresponding muscles to be stimulated;

[0031] iteration for M times, preferably two times, of cycles of a number Ni of repetitions, wherein i is the i-th repetition, of data acquisition phases during which the central unit actuates the stimulation means in such a way to produce periodical contractions of the muscles with a constant frequency for a &Dgr;t, preferably between 5 and 10 seconds, with a progressively growing frequency, from a repetition to the following one and included between the lower limit frequency and the upper limit frequency, frequencies of consecutive repetitions having each other a constant difference &Dgr;ƒi, the central unit processing, for each repetition, the average of th amplitude of signals coming from the detectors and memorizing it within the memory unit along with the value of the corresponding frequency, the central unit determining for each iteration i the maximum sum of the average of the amplitudes of the signals detected and individuating the corresponding best frequency for each iteration i, following the first one, the range between the first lower frequency and the second upper frequency comprising the best frequency individuated at the preceding iteration, for each iteration i, following the first one, the constant difference &Dgr;ƒi between the consecutive repetition frequencies being lower than the difference &Dgr;ƒi−1 of the preceding iteration (&Dgr;ƒi<&Dgr;ƒi−1); and

[0032] determination of the optimum frequency at the end of the M-th iteration, wherein the best frequency individuated at the M-th iteration is memorized as the optimum frequency.

[0033] Preferably, according to the invention, for the first iteration, the first lower frequency coincides with the lower limit frequency and/or the second upper frequency, with the upper limit frequency.

[0034] Still preferably according to the invention, for each iteration i following to the first one, the range between the first lower frequency and the second upper frequency comprises the best frequency individuated at the preceding iteration as intermediate frequency.

[0035] Furthermore, according to the invention, the automatic device can also comprise an input/output interface, preferably comprising a display.

[0036] The central unit can visually display signals detected by detectors and the value of the optimum frequency individuated.

[0037] Still according to the invention, the device can provide, by the interface, manual setting selection of the periodical contractions of the muscle.

[0038] Furthermore, according to the invention, the interface can be provided with reading and/writing devices for removable memory media, for storing data pertaining to an individual user.

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The present invention will be now described, for illustrative but not limitative purposes, according to its preferred embodiments, with particular reference to the figures of the enclosed drawings, wherein:

[0040] FIG. 1 shows a block diagram of the preferred embodiment of the device according to the invention;

[0041] FIG. 2 shows the time run of the signal detected by the device of FIG. 1, applied to the lateral crureus muscle; and

[0042] FIG. 3 shows the time run of the signal detected by the device of FIG. 1, applied to the front tibialis muscle.

DETAILED DESCRIPTION

[0043] In the following explicit reference will be made for illustrative but not limitative purposes to an embodiment of the device according to the invention the stimulation means of which are mechanical means. However, it must be noted that other embodiments of the device according to the present invention can provide that the muscular stimulation means are electrical or electro-mechanical means, within the scope of the present invention.

[0044] Making reference to FIG. 1, it can be noted that the preferred embodiment of the device according to the invention comprises a central electronic unit 1, connected to a memory unit 2 and to an input/output interface 3. Central unit 1 is also connected to a detector 4 of muscular electric activity and to mechanical stimulation mechanical means 5.

[0045] Detector 4 comprises medical electrodes 6, amplified in situ, an insulation amplifier and a signal converter providing at the output a digital signal read by the central unit 1.

[0046] Mechanical means 5 provides, in the preferred embodiment, for the stimulation of the leg muscles, a support structure on which a jumpy board is placed, comprising a metallic plate resting on rubber shims allowing its vibration. Two engines are coupled with the plate, having eccentric masses, able to produce the vibration of the plate, piloted by an electronic device comprising an inverter connected to a potentiometer adjusting the vibration frequency, the central unit setting said vibration frequency. Particularly, central unit 1 sets said vibration frequency. The support structure can provide a rod or handle for the user.

[0047] The vibration mechanical frequency of the mechanical means 5 of the stimulation is controlled to coincide with the frequency of the periodical contractions of the muscle induced by the stimulation.

[0048] Central unit 1 manages and controls all the components of the automatic device, processing data coming from detector 4 in such a way to determine within said range included between a lower limit frequency, preferably equal to 1 Hz, and an upper limit frequency, preferably 1000 Hz, the optimum vibration frequency of the tilting board in correspondence of which the specific muscle has the maximum response to the stimulation and consequently setting vibration frequency of the mechanical means 5.

[0049] In a first embodiment of the device according to the invention, it is provided a method for the determination of the optimum frequency comprising the phases of:

[0050] application, in a conventional way, of the medical electrodes 6 of the detector 4 to the muscles to be stimulated;

[0051] repetition for N times, N being preferably eight times, of a data acquisition phase during which the central unit 1 actuates the vibration with a constant frequency of the mechanical means 5 for a &Dgr;t time, &Dgr;t being preferably between 5 and 10 seconds, with a progressively growing vibration frequency, from a repetition to the following one and included between the lower limit frequency and the upper limit frequency, processing, for each repetition, the average of the amplitude of signals coming from detector 4 and memorizing the same within the memory unit 2 along with the value of the corresponding vibration frequency;

[0052] determination of the maximum electrical response for which the central unit 1 determines among those memorized, the average having a maximum value, consequently individuating the optimum vibration frequency, for which the specific muscle has the maximum response.

[0053] Preferably, frequencies of consecutive repetitions during the data acquisition have a constant difference; however, it can be provided also a variable and increasing difference as a function of the absolute value of the frequency of the preceding repetition.

[0054] Once the optimum frequency is determined, the muscular stimulation phase is started, during which the central unit 1 activates vibration of mechanical means 5 with said optimum frequency for a predetermined time or for a time selectable by the user by interface 3.

[0055] For example, FIGS. 2 and 3 show the signal detected by detector 4, during the execution of the described method for determining the optimum frequency, during which medical electrodes are respectively applied to the lateral crureus muscle and to the front tibialis muscle of an user. Particularly, number of repetitions provided is 6 (N=6) and duration of the constant vibration frequency of the mechanical means 5 is 10 seconds (&Dgr;t=10). Vibration frequencies of the six repetitions are 22.5 Hz, 25 Hz, 27.5 Hz, 30 Hz, 32.5 Hz and 35 Hz, respectively.

[0056] It is evident from the above figures that optimum frequency (frequency at which average of amplitude has maximum value) for the lateral muscle is the fourth one, i.e. 30 Hz, while for the front tibialis muscle is the third one, i.e. 27.5 Hz.

[0057] Particularly, lower limit frequency and upper limit frequency could be variable in function of the specific fibers of the particular muscle to be stimulated, and settable by the interface 3.

[0058] A second preferred embodiment of the device according to the invention provides that the method for determining the optimum frequency, comprising the following phases:

[0059] application in a conventional way of the medical electrodes 6 of the detector 5 to the muscles to be stimulated;

[0060] iteration for M times, M being preferably two times, of cycles of a number Ni of repetitions, wherein i is the i-th repetition, of data acquisition phases during which the central unit 1 actuates the constant frequency vibration of the mechanical means 5 for a time &Dgr;t, &Dgr;t being preferably equal to 10 seconds, with a progressively growing frequency, from each repetition to the following one, and included between the lower limit frequency and the upper limit frequency, frequencies of consecutive repetitions having a constant difference &Dgr;ƒi, where preferably, for the first iteration, first lower frequency coincides with the lower limit frequency and/or the second upper frequency coincides with the upper limit frequency, central unit 1 processing, for each iteration i the average of the amplitude of the signal coming from the detector 4 and storing the same within the memory unit 2 along with the value of the corresponding vibration frequency, the central unit 1 determining for each iteration i the average with the maximum value and determining the corresponding best frequency for each iteration i, following the first one, the range between the first lower frequency and the second upper frequency comprising the best frequency identified at the preceding iteration, for each iteration i, following the first one, the constant difference &Dgr;ƒi between the consecutive repetition frequencies being lower than the difference &Dgr;ƒi−1 of the preceding iteration (&Dgr;ƒi<&Dgr;ƒi−1); and

[0061] determination of the optimum frequency at the end of the M-th iteration, wherein the best frequency individuated at the M-th iteration is memorized with the optimum frequency for which the maximum response has the best response.

[0062] In other words, method described in the above determines optimum frequency identification, by a progressively better resolution, the vibration frequency for which the specific muscle has the maximum response. Said method is faster with the cost of a slightly higher processing load.

[0063] Preferred embodiments of the device according to the invention provide visualization by the interface 3 that can comprise a display for signal detected by detector 4 and of the value of the optimum frequency individuated.

[0064] Other preferred embodiments can provide that the user can select manual setting of the vibration frequency by interface 3.

[0065] Further preferred embodiments can provide that values of optimum frequencies corresponding to the various muscles of a same user are memorized on removable memory devices, such as magnetic cards and/or optical discs, by interface 3, to be then read by interface, avoiding further executions of the method for the determination of the optimum frequency. Eventually, optimum frequencies corresponding to an user can be memorized within memory unit 2 and recalled by association, and insertion by interface 3, of an identification code of the user.

[0066] Other embodiments can provide that muscular stimulation mechanical means provide a oscillating, rather than jumpy, board, or vibrating means.

[0067] Still, further preferred embodiment can provide more than one muscular electrical activity detector, each one applied to one muscle of the user, to stimulate different muscles at the same time. For example, different muscles of a leg can be stimulated inducing contractions at the frequency for which the whole of the responses from the muscles on which are applied the detectors is bigger. In this case, interface 3 can visualize on display all the signals detected by the detector.

[0068] Said embodiments can be used for diagnostic uses. For example, detectors can be applied on homologous muscles of the two upper limbs or of the two lower limbs. During the execution of the method for the determination of the optimum frequency, in case that one of the two limbs has been subjected to surgical intervention, and thus a mechanical insult has been made on the biological tissue (for example muscles and/or chorda and/or capsule and/or ligaments), response detected for the limb subjected to a surgical intervention is different with respect to the laudable one. Amount of the response difference of the two limbs indicates the amount of the difference of response of propioceptors ad, thus, amount of damage received from the person at the limb subjected to surgical intervention.

[0069] The present invention has been described for illustrative but not limitative purposes, according to its preferred embodiments, but it is to be understood that modifications and/or changes can be introduced by those skilled in the art without departing from the relevant scope as defined in the enclosed claims.

Claims

1. A device for optimized muscular stimulation, the stimulation providing periodical contractions with constant frequency of one or more muscles of a user, the device comprising:

a central electronic unit;

a memory unit connected with the central electronic unit;

a muscular electrical activity detector for application to a muscle of the user to be subjected to stimulation, for producint a muscular activity signal; and

muscular stimulation means actuated by the central unit,

the central electronic unit configured to receive the muscular activity signal from the detector in and to determine, within a range included between a lower limit frequency and an upper limit frequency, an optimum frequency of the periodical contractions in correspondence of which the amplitude of the signal provided by the detector is a maximum amplitude, the central unit further configured to control the muscular stimulation means to produce periodical contractions of the muscle to be stimulated at the determined optimum frequency.

2. The device according to claim 1, characterized in that the lower limit frequency is 1 Hz.

3. The device according to claim 1, characterized in that the upper limit frequency is 1000 Hz.

4. The device according to claim 1 wherein the muscular stimulation means are mechanical means.

5. The device according to claim 4, wherein:

the mechanical means comprises a support structure on which a board is placed upon which the user is positioned, comprising a metallic plate and a motor connected with the plate and having an eccentric mass.

6. The device according to claim 4, characterized in that mechanical means comprises a tilting board.

7. The device according to claims 1, characterized in that the muscular stimulation means are electrical means.

8. The device according to claim 1, wherein the detector comprises a medical electrode, amplified in situ, an isolation amplifier and a signal converter providing at the outlet a digital signal read by the central unit.

9. The device according to claim 1 wherein the central unit is configured to execute a method of determining said optimum frequency comprising the phases of:

repetition for N times of a data acquisition phase during which the central unit actuates the stimulation means in such a way to produce periodical contractions of the muscle with a constant frequency for a &Dgr;t, with a progressively growing frequency, between the lower limit frequency and the upper limit frequency,

processing, for each repetition, the amplitude of the signal coming from the detector and memorizing the same within the memory unit along with the value of the corresponding frequency; and

determining the maximum amplitude of signal produced by the detector, wherein the central unit determines, among the memorized data, the frequency corresponding to the maximum value, to identify the optimum frequency.

10. The device according to claim 9, characterized in that N is equal to eight.

11. The device according to claim 9, wherein &Dgr;t is at least 5 seconds.

12. The device according to claim 9, characterized in that &Dgr;t is at least 10 seconds.

13. The device according to claim 9, wherein consecutive repetition frequencies have a constant difference.

14. The device according to one of the claims from 9, wherein consecutive repetition frequencies have a variable difference, increasing as a function of the absolute value of the frequency of the preceding repetition.

15. The device according to one of the claim 1 wherein in that the central unit performs a determination method of the optimum frequency, comprising the steps of:

iterating for M times of cycles of a number Ni of repetitions, wherein i is the i-th repetition, of data acquisition phases during which the central unit actuates the stimulation means in such a way to produce periodical contractions of the muscles with a constant frequency for a &Dgr;t, with a progressively growing frequency, between a lower limit frequency and an upper limit frequency, frequencies of consecutive repetitions having each other a constant difference &Dgr;ƒi,

receiving the amplitude of the signal coming from the detector and memorizing it within the memory unit along with the value of the corresponding frequency,

determining for each iteration i the maximum of the amplitude of the signal detected and identifying a corresponding optimum frequency for each iteration i,

determining the range between a lower frequency and an upper frequency comprising the optimum frequency identified during the preceding iteration, wherein for each iteration i, a constant difference &Dgr;ƒi is applied between the consecutive repetition frequencies being lower than the difference &Dgr;ƒi−1 of the preceding iteration (&Dgr;ƒi<&Dgr;ƒi−1); and

determining an optimum frequency at the end of the M-th iteration, wherein the best frequency individuated at the M-th iteration is memorized as the optimum frequency.

16. The device according to claim 15, characterized in that M is equal to two.

17. The device according to claim 15, characterized in that &Dgr;t is equal to 5 seconds.

18. The device according to claim 16 or 17, characterized in that &Dgr;t is equal to 10 seconds.

19. The device according to claim 15, characterized in that for the first iteration, the first lower frequency coincides with the lower limit frequency and/or the second upper frequency, with the upper limit frequency.

20. The device according to claim 15, characterized in that for each iteration i following to the first one, the range between the first lower frequency and the second upper frequency comprises the optimum frequency individuated at the preceding iteration as an intermediate frequency.

21. The device according to claim 1, comprising an input/output interface.

22. The device according to claim 21, wherein the interface comprises a display.

23. The device according to claim 22, wherein the central unit is configured to provide the detector signal to the display, and to provide the identified optimum frequency to the display.

24. The device according to claim 21, wherein the interface provides means for selecting the periodical contractions of the muscle.

25. The device according to 21, wherein the interface comprises means for reading a removable memory medium.