JP2009225810A - Electrical muscle stimulation method and muscle training device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a muscle training device which makes a user expect higher exercising effects with a higher safety of exercising by preventing the awkwardness of the user's motion and the user's feeling of uneasiness in motion in the exercising of joints associated with the stretching or bending of hands, elbows, foot joints, a trunk and the like under a closed motion chain. <P>SOLUTION: The muscle training device (A) includes an instrument (1) having electrode parts (10 and 11) for applying electrical stimulus onto the muscle, an angle detector (2) for detecting the angle of each stretched or bent site, a controller (3) for supplying electricity to the electrode parts (10 and 11), and a computer (4) for controlling the controller (3). The computer (4) includes a program which controls the intensity of electrical stimulation to be applied onto antagonistic muscles so as to generate a contraction force sufficiently smaller than the contraction force of mainly moving exercised muscles in the initial exercising period in the antagonistic muscles based on the information detected with the angle detector (2) and this enables the optimal contraction of the antagonistic muscles previously determined for each angle of sites toward the final end stage of exercising. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a muscle electrical stimulation method and a muscle training device. More specifically, in the exercise of extending or flexing joints such as hands, elbows, knees, ankles, and trunks by the closed movement chain, for example, even with the same strength of electrical stimulation, the muscle contraction force varies depending on the joint angle. By taking into account and controlling the strength of the electrical stimulation, the user's movement becomes unnatural and prevents the user from feeling uncomfortable. The present invention relates to a method for electrically stimulating muscle and a muscle training device.

  Conventionally, as a muscle training device (muscle strength enhancer) using electrical stimulation, there have already been proposed by the present inventors (see Patent Documents 1 and 2). This muscle training device, when the muscle serving as the main muscle is contracting, applies electrical stimulation to the muscle serving as the antagonist muscle to cause centrifugal contraction (hereinafter referred to as “closed motion”). Called “exercise”).

  According to this closed exercise, unlike the general exercise that loads a muscle with a heavy object such as a dumbbell, it is safe to apply a load to the main and antagonist muscles simultaneously without using a heavy object. In addition, the user's muscular strength can be maintained or enhanced.

  In the claims and the description, the “main muscle” refers to a muscle that contracts and stretches and bends the joints such as the knee and elbow, and the “antagonist muscle” refers to the knee and elbow depending on the main muscle. This refers to the muscle that stretches when the joint is stretched and bent. In other words, the main and antagonist muscles work against each other and simultaneously perform opposite movements.

Patent 3026007 JP-A-2005-253539

By the way, the above-mentioned closing exercise is to make the resistance to movement by causing muscle contraction by electrical stimulation to the antagonist muscle, but the present inventors have further researched on the closing exercise. However, it has been found that when electrical stimulation of the same strength is performed, the contraction force of the stimulating muscle differs depending on the angle of the joint that extends or bends.
Specifically, in the biceps, which is a muscle that moves the elbow joint, for example, the maximum contractile force can be obtained when the bending angle of the elbow joint (how many times the extension state is bent at 0 degree) is 60 degrees. This value is about twice the contraction force when the bending angle is 0 degree (see Table 1).

  In addition, the contraction force of the muscle differs depending on the strength of the electrical stimulation. For example, in the biceps, when the voltage is reduced by 20% (when the reference is 45V: 100%, it becomes 36V), the muscle contraction. It was also found that the force was less than half (see Table 2). That is, it has been found that, for example, the contractile force of the muscle can be adjusted by changing the strength of the applied voltage to control the strength of the electrical stimulation.

From these studies, simply applying a constant voltage electrical stimulus to the antagonist muscles does not provide a certain muscle contraction force or a muscle contraction force favorable to exercise, and as the joint angle changes due to exercise, It was found that there is a possibility that the movement becomes unstable.
Specifically, in the upper arm exercise, as described above, the maximum muscle contraction force generated by electrical stimulation occurs when the bending angle of the elbow joint is 60 degrees, and is about 50% at 0 degrees. When exercise is performed to extend the elbow joint from a bent state (for example, a flexion angle of 90 degrees), an exercise resistance of about 60% of the maximum value occurs at the beginning of the exercise, and an exercise with a maximum value of 100% in the middle period (flexion angle of 60 degrees). At the end of the period when resistance occurs and approaches the extension state at the end of exercise, the exercise resistance is about 50% of the maximum value. That is, the exercise resistance due to the antagonist muscle greatly fluctuates during the extension exercise. With this, natural exercise cannot be performed, and the user who exercises feels uncomfortable.

  In order to solve this problem and enable more natural movement, it is one way to generate a constant movement resistance from the beginning to the end of the movement, such as dumbbell movement, but rather, It is practical and preferable to generate a smaller resistance in the initial stage of exercise, such as a tube movement, which is said to have a higher exercise effect, and to generate a greater resistance in the middle and final stages of exercise.

In addition, if the resistance of the antagonistic muscles due to electrical stimulation during exercise causes contraction that is too large for the user, the contraction force of the main muscles due to spontaneous movement may be reduced. In this case, movement occurs in a direction opposite to the intended movement direction, and this movement information is also acquired by a sensor (encoder or the like) that senses the movement of the joint.
Thereby, the muscle contraction by the electrical stimulation which becomes the movement resistance of the exercise | movement to an opposite direction generate | occur | produces. The user who is trying to resist the opposite movement is assisted by this, and again performs spontaneous movement in the intended direction, but this movement is immediately detected by the sensor, and the contraction force of the main muscle again antagonizes. The situation is less than the muscle contraction force. In this way, it becomes easy to cause a movement that repeats small bending and stretching, and it makes a jerky and unstable movement, and not only does the target movement become impossible, but also there is a risk of damaging muscles and joints.

Furthermore, the state of muscle expansion and contraction also becomes a problem. That is, when muscle contraction due to electrical stimulation occurs while the muscle is relaxed, for example, muscle contraction due to electrical stimulation in a portion not involved in joint motion occurs, and muscle contraction and joint motion are not immediately linked, There is a delay before the muscle contraction due to electrical stimulation becomes joint motion. On the other hand, during this period, the movement of the main muscle does not receive resistance due to the muscle contraction due to the electrical stimulation of the antagonist muscle, and therefore the movement is performed by the relatively weak spontaneous muscle contraction. Thereafter, when the antagonistic muscles become tense and become involved in joint movement, the muscle contraction due to the electrical stimulation that has occurred so far is coupled with the sudden movement resistance.
In such a state, spontaneous muscle contraction temporarily increases in order to resist the force of antagonistic muscle contraction, but when the muscle contraction and joint motion are balanced, the large spontaneous muscle contraction is contracted by electrical stimulation. It becomes too large and becomes a fast joint movement, so it reduces spontaneous muscle contraction to suppress it unconsciously. Then, it antagonizes the muscle contraction force due to the electrical stimulation, and the joint motion is stopped, and the electrical stimulation is also stopped by the information of the encoder. This is repeated several times, and the movement may become unstable. In particular, this phenomenon is likely to occur when the stimulation voltage is high.

(Object of the present invention)
Accordingly, an object of the present invention is to perform muscle contraction that varies depending on the angle of the joint even with electrical stimulation of the same strength in the exercise of extending or bending joints such as hands, elbows, knees, ankles, and trunks by a closed chain of motion. By controlling the strength of the electrical stimulation in consideration of the force, the contraction force of the antagonistic muscle that becomes resistance to movement does not become too large and the contraction force of the main muscle does not fall, so that the user's exercise Muscle electrical stimulation method and muscle training device that can prevent unnaturalness and users from feeling uncomfortable with exercise, improve exercise safety, enable smooth exercise and also improve exercise effect Is to provide.

  The means of the present invention taken in order to solve the above problems are as follows.

(1) In the present invention, when the muscle that is the main muscle is contracting, the movement that extends or bends the joint by the closed motor chain that applies electrical stimulation to the muscle that becomes the antagonistic muscle to perform centrifugal contraction. In
Based on information on joint angles that change with exercise, within the predetermined range of electrical stimulation that the user can withstand, the muscles of the main muscle during exercise are contracted against antagonistic muscles at the beginning of exercise. Give the antagonistic muscle an electrical stimulus that produces a contraction force that is sufficiently smaller than the force, and gradually increase the strength of the electrical stimulus toward the end of exercise, or This is an electrical stimulation method for muscles, which is determined in advance for each angle, and gives an electrical stimulation of strength that can provide a suitable muscle contraction to the antagonist muscle.

(2) The present invention provides a muscle training device that can train the main and antagonist muscles in parallel by applying electrical stimulation to the antagonist muscles and contracting them when the main muscles contract and the antagonist muscles extend. Because
A brace equipped with an electrical stimulation unit for applying electrical stimulation to muscles;
An angle detection means for detecting the angle of the joint that performs extension or bending movement;
An electric supply unit for supplying electricity to the electrical stimulation unit;
A computer for controlling the electricity supply unit;
With
The computer
Based on the information for calculating the angle of the joint that changes with movement, detected by the angle detection means, within the range of the predetermined electrical stimulation strength that the user can withstand, against the antagonist muscle In the initial stage of exercise, the electrical stimulation unit gives an electrical stimulus of strength that causes the antagonistic muscle to produce a contraction force sufficiently smaller than the contraction force of the main muscle during exercise, and the strength of the electrical stimulus toward the end of exercise It has a program to control to gradually strengthen,
It is a muscle training device.

(3) The present invention provides a muscle training device that can train the main and antagonist muscles in parallel by applying electrical stimulation to the antagonist muscles and contracting them when the main muscles contract and the antagonist muscles expand. Because
A brace equipped with an electrical stimulation unit for applying electrical stimulation to muscles;
An angle detection means for detecting the angle of the joint that performs extension or bending movement;
An electric supply unit for supplying electricity to the electrical stimulation unit;
A computer for controlling the electricity supply unit;
With
The computer
Based on the information for calculating the angle of the joint that changes with movement, detected by the angle detection means, within the range of the predetermined electrical stimulation strength that the user can withstand, against the antagonist muscle In the early stage of exercise, the electrical stimulation unit gives an electrical stimulus of strength that causes the antagonistic muscle to produce a contraction force sufficiently smaller than the contraction force of the main muscle during exercise, and for each joint angle toward the end of exercise A program for controlling the antagonistic muscle to give an electrical stimulus having a strength that can provide a suitable muscle contraction to the antagonistic muscle is provided.
It is a muscle training device.

(4) The muscle training device according to the present invention senses the movement based on the information acquired by the angle detection means when an unstable movement occurs in the movement of the user in the computer, and the electrical stimulation It is also possible to provide a program for controlling to reduce the intensity of the electrical stimulation by the unit or to stop the electrical stimulation.

(5) The muscle training device according to the present invention includes a monitor, and displays on the monitor an image of a model that performs an exemplary movement of the user's exercise on the computer, and detects the angle according to the user's exercise. A program for calculating an evaluation of the movement of the model based on information acquired by the means and displaying the evaluation on the monitor may be provided.

(6) A muscle training device according to the present invention includes a monitor, and calculates, on a computer, a user's movement based on information acquired by the angle detection means according to the user's movement, It is also possible to provide a program for displaying on the monitor as an image.

The term “electrical stimulation” in the claims and specification is used to include the meaning of applying a required voltage to a muscle and applying a required current to stimulate the muscle. Further, the control of the intensity of the electrical stimulation can be performed by controlling the applied voltage or by controlling the current.
In addition, the term “increase gradually” in the claims and the specification is used to include the meaning of “increase gradually or gradually, steplessly or steplessly”. Yes.
Furthermore, the terms “joint bending angle” and “joint angle” in the specification are, for example, 0 degrees when the elbow joint, the knee joint or the trunk is extended (when the trunk becomes essentially straight). It is used to mean the bending angle from

(Function)
The operation of the muscle training device according to the present invention will be described. According to the muscle training device, training of not only joints such as hands, elbows, knees and ankles, but also trunk (torso) muscles (vertical spine, rectus abdominis, left and right external obliques) Is possible.

  The muscle training device, for example, gradually increases the strength of the electrical stimulation to the antagonist muscles (for example, gradually increases the applied voltage) or the part as the joint moves or moves in the bending direction. The angle is changed so as to give an electrical stimulus having a strength that provides a suitable muscle contraction to the antagonistic muscle, which is predetermined for each angle. In this way, by gradually increasing the strength of the electrical stimulation and controlling the strength of the electrical stimulation according to the angle of the part, the user gradually increases the exercise resistance, such as tube exercise A natural feeling is obtained.

  In addition, since the antagonistic muscle generates a contraction force sufficiently smaller than the contraction force (for example, the maximum contraction force) of the main muscle during exercise in the initial stage of exercise, the spontaneous movement by the main muscle cannot resist the exercise resistance due to the contraction of the antagonist muscle. You can also avoid the situation where you stop. As a result, it is possible to prevent the target exercise from becoming impossible due to the jerky and unstable movement that repeats small bending and stretching at the beginning of the exercise, and to prevent the muscles from being damaged, and the exercise can be started in a stable state. . In addition, since the strength of the electrical stimulation given to the antagonistic muscle is controlled (adjusted) based on the information on the joint angle that changes with exercise, the user can set the voltage rise time short. It is difficult to feel a sudden muscle contraction, thereby contributing to the stability of the exercise.

  A monitor is provided on the computer, and an image of a model that exhibits a typical movement of the movement performed by the user is displayed on the monitor, and the model of the model is based on information acquired by the angle detection means according to the movement of the user. A muscle training device having a program for calculating an evaluation of movement and displaying the evaluation on the monitor so that the user observes the evaluation displayed on the monitor during exercise and adjusts his movement to the movement of the model. Can be corrected. Thereby, it is possible to perform a more effective exercise with no waste and accuracy. In addition, since the evaluation is improved by performing an exercise closer to the ideal exercise of the model, for example, the exercise for rehabilitation can be performed happily like a game, and the user can easily maintain the motivation for the exercise. .

  A muscle having a monitor, and a computer having a program for calculating a user's movement based on information acquired by the angle detection means according to the user's movement and displaying the movement on the monitor as a model image The training device allows the user to exercise while recognizing the movement of the model displayed on the monitor as his / her movement. Thereby, even when the user is performing an unnatural and awkward exercise, the user can correct the movement so that the user can move naturally and smoothly.

  As described above, an excessively high stimulation voltage causes unstable movement. When the stimulation voltage is set, even if it can withstand the stimulation voltage, when muscle contraction occurs due to the stimulation voltage during exercise, the muscle strength (contraction force) of the main muscle is the muscle strength (contraction force) due to the electrical stimulation of the antagonistic muscle. May be lower. In particular, it tends to occur in the movement of the lower limb (leg thigh).

  In many cases, this phenomenon can be eliminated by weakening the stimulation voltage. Therefore, when an unstable movement (for example, repeated slight bending and stretching) occurs in the user's movement in the computer, the movement is detected based on the information acquired by the angle detection means, and the electric stimulation unit By providing a program that reduces the intensity of electrical stimulation or stops electrical stimulation, a mechanism (safe mode) such as automatically reducing the maximum applied voltage by 20% can be incorporated. Stable movement can be stopped. The safe mode may be automatically canceled when a break is entered, or may be arbitrarily canceled during exercise.

According to the present invention, for example, with the movement of the joint in the extension or bending direction, the strength of the electrical stimulation to the antagonist muscle is gradually increased, or is determined in advance for each part angle. Change the intensity of the electrical stimulation to give a suitable muscle contraction to the muscle, gradually increase the intensity of the electrical stimulation, or adjust the strength of the electrical stimulation according to the angle of the part. By controlling, the user can get a natural feeling that the motor resistance gradually increases.
In addition, since the antagonistic muscle generates a contraction force sufficiently smaller than the contraction force of the main muscle during exercise in the initial stage of exercise, there are situations where the spontaneous movement by the main muscle loses without being able to counter the motor resistance due to the contraction of the antagonist muscle. Can be avoided. As a result, it is possible to prevent the target exercise from becoming impossible due to the jerky and unstable movement that repeats small bending and stretching at the beginning of the exercise, and to prevent the muscles from being damaged, and the exercise can be started in a stable state. .
Furthermore, even if the rise time of the voltage is set short by controlling (adjusting) the strength of the electrical stimulation applied to the antagonistic muscle based on information on the joint angle that changes with exercise, the user Can hardly feel a sudden muscle contraction, which can contribute to the stability of exercise.
Therefore, it is possible to prevent the user's movement from becoming unnatural and the user from feeling uncomfortable with the movement, to improve the safety of the movement, and to enable smooth movement and to improve the movement effect. it can.

Embodiments of the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a schematic explanatory diagram of a muscle training device according to the present invention.
FIG. 2 is an explanatory view showing a mounting state of the angle detector.

  The muscle training device A performs, for example, a wrist joint (finger), an elbow joint, a knee joint, an ankle joint, a trunk joint, and other joints that extend or bend. (Minor lateral and extensor carpal flexors, ulnar carpal extensors and ulnar carpal flexors, etc.), elbow joint exercise, upper arm muscles (biceps, triceps, etc.), knee For joint movement, the thigh muscles (quadriceps, biceps, half-tendonoid, half-membranous muscle, etc.), and for the ankle movement, the lower leg muscles (anterior tibial muscle, long thumb) Extensors, long finger extensors, gastrocnemius, soleus, etc., for trunk exercises, abdominal, dorsal, and lateral muscles (stratus abdominal muscle, spine standing muscle, left and right internal oblique muscles, external oblique muscles, etc.) It is something that can be trained.

Reference is mainly made to FIG.
The muscle training device A includes electrode units 10 and 11 (which constitute an electrical stimulation unit) that apply electrical stimulation to muscles, and includes a brace 1 that can be worn on an upper limb (arm) and a lower limb (leg), and exercise. The angle detector 2 detects the angle of the joint that changes due to the above, a controller 3 that constitutes an electricity supply unit that supplies electricity to the electrode units 10 and 11, and a computer 4 that controls the controller 3.

(Appliance 1)
The brace 1 will be described here by taking the brace worn on the upper limb as an example. The brace 1 is formed of a material having flexibility and stretchability as a base material, and has a deployable belt shape (or belt shape) that becomes a cylindrical shape when attached in a state of being in close contact with the upper arm portion. Examples of the material for forming the brace 1 include jersey (a stretchy thick knitted fabric), sponge rubber, non-woven fabric, and the like, and these can be used alone or in combination.

  On the inner surface side of the brace 1, there are provided electrode portions 10 and 11 for applying electrical stimulation by applying a controlled voltage to muscles that are antagonistic muscles during exercise while in contact with the user's skin. Each of the electrode portions 10 and 11 is provided at a muscle motor point (a point at which the muscle can be contracted most efficiently when the muscle is electrically stimulated), and is brought into close contact with the skin by a conductive gel. . The electrode portion 10 corresponds to the biceps brachii when the appliance 1 is worn, and the electrode portion 11 is provided at a position corresponding to the triceps surae.

The electrode units 10 and 11 are connected to the power supply unit 30 of the controller 3 by a power supply cable 32 (shown in FIG. 1 and not shown in FIG. 2).
Note that the brace is not limited to the belt-like brace 1. For example, a bracelet that can be worn on the upper body (for upper limbs), or a lower-bore-shaped brace that can be worn on the lower body (lower limbs). Etc.) and other structures may be used.

(Angle detector 2)
Reference is mainly made to FIG.
The angle detection tool 2 that is an angle detection means includes an encoder 20, an upper arm attachment tool 21, and a forearm attachment tool 22. The encoder 20 employed in the present embodiment is a linear encoder having a function of measuring the moving distance of the object by the amount of the wire 23 drawn, but an encoder having another structure has a similar function. Can also be adopted. Note that the angle detector 2 including the encoder 20 does not detect the joint bending angle itself as described later, but obtains information for calculating the joint bending angle by the computer 4.

  The encoder 20 is attached to the outer surface side of the upper arm attachment 21 and is connected to the controller 3 by a data transmission cable 33. The upper arm wearing tool 21 is formed in a belt shape, and can be wound around the brace 1 mounted on the upper arm portion at an appropriate position. The forearm wearing tool 22 is also formed in a belt shape and can be wound around the forearm at an appropriate position. The distal end portion of the wire 23 drawn out from the encoder 20 can be attached to an appropriate position of the forearm mounting tool 22.

  When the upper arm wearing tool 21 and the forearm wearing tool 22 are attached to the user's arm and the elbow joint is extended or bent, the encoder 20 corrects the amount of the wire 23 that goes in and out with the movement. Detect in the reverse direction. This information is counted by the controller 3 as will be described later, and this count value is sent to the computer 4. The computer 4 calculates the angle of the elbow joint in real time based on this information (count value), and sends various control information such as an applied voltage predetermined for the angle to the controller 3.

  The control using the encoder 20 is provided with so-called “play” in the sense of delaying the timing of applying a voltage (applying electrical stimulation) to the muscle (shifting the timing). If the user starts exercise and immediately applies electrical stimulation to the antagonist muscles to contract the antagonist muscles, the exercise tends to become unstable. In addition, when the speed of movement in the direction of bending or extension of the joint is reduced or stopped for a very short time, it is considered that this is regarded as a stop of motion, and the electric stimulus is not applied, which causes the motion to become unstable.

  As countermeasures, the slight movement of the encoder at the start of movement is not regarded as movement, and the voltage is instantaneously applied by, for example, 0.2 seconds before reaching the maximum voltage when applying the voltage. I tried not to raise it. A very short stop or minute movement of the encoder during movement is not regarded as a stop of movement, and electrical stimulation is continued between them. In addition, by setting the play of the encoder that is optimal for exercise at each part of the elbow joint, knee joint, and trunk, it is possible to easily cope with different exercise ability depending on the user.

(Controller 3)
The controller 3 includes a power feeding unit 30 (shown in FIG. 3 to be described later) for supplying electricity to the electrode units 10 and 11 provided in the appliance 1 (for applying a stimulation voltage). In addition, the controller 3 includes a communication unit 31 for exchanging information with the computer 4. The controller 3 sends the count value counted based on the information from the encoder 20 of the angle detector 2 to the computer 4. Moreover, the control information sent from the computer 4 is acquired, and a voltage suitable for the bending angle of the joint during exercise is applied to the electrode units 10 and 11 in real time based on this information.

(Computer 4)
The computer 4 is a general-purpose notebook computer (notebook personal computer) configured to include an arithmetic device, a storage device, and the like. The computer 4 includes a monitor 40 that is a display device, and includes a communication unit 41 for exchanging information with the controller 3.
The computer 4 is assembled so that information can be exchanged wirelessly with the controller 3. Note that the exchange of information is not limited to wireless communication, and may be wired using a communication cable. Furthermore, it is possible to exchange data with an external computer using a LAN (Local Area Network) or the Internet.

  The storage device (not shown) of the computer 4 stores (a) the joint angle (joint bending angle, etc.) that changes with the user's movement based on the information (count value) sent from the controller 3. A calculation program, (b) a program for controlling the controller 3 so as to give an electrical stimulation of a strength that is determined in advance for each angle of the region and that provides a suitable muscle contraction to the antagonist muscle, and (c) is calculated A program for creating a model image (virtual image) based on the information on the angle of the part and displaying it on the monitor 40, (d) a program for creating a model image showing an exemplary movement and displaying it on the monitor 40, ( e) Various programs such as a program for calculating an evaluation of the user's movement with respect to an exemplary movement of the model and displaying the evaluation as a graph on the monitor 40 are stored. It has been.

  In the virtual image displayed on the monitor 40, several modes with different model displays are set. For example, in addition to a mode (see FIG. 6) in which a model 42 that performs an exemplary movement is displayed at the top of the screen and a model 43 that samples and moves the user is displayed at the bottom of the screen (see FIG. 6), the model 42 performs an exemplary movement. These include a mode in which the model 42 can be viewed from various directions, and a mode in which the model 43 that moves in synchronization with the movement of the user can be viewed from various directions.

  Further, by setting exemplary exercise data in advance and comparing the data with this data in real time, the user's exercise can be evaluated. The angle evaluation graph 44 displayed on the right side of the middle stage of the screen changes the length and color of the graph on the screen according to the change in the bending angle of the joint accompanying the movement. The graph becomes longer as the bending angle of the joint becomes larger and becomes shorter as it becomes smaller. Note that the graph is displayed in red if the bending angle of the joint is not sufficient for the movement of the model 42 that performs the model movement (if the bending method is insufficient), and if it is sufficient, the graph is displayed in blue.

  Furthermore, the exercise evaluation graph 45 displayed at the bottom of the screen is a graph (upper row) that evaluates how close the exercise is to the model movement, and a graph (lower row) that evaluates how much the exercise can be achieved. It is configured. The user can move closer to the ideal movement and increase the evaluation of the exercise by exercising with the intention of correcting the movement while viewing the evaluation graphs 44 and 45 on the screen of the monitor 40. It is possible to enjoy exercising like a game and to maintain motivation.

(Function)
FIG. 3 is a flowchart from joint angle detection to electrical stimulation during exercise.
FIG. 4 is a flowchart showing control of electrical stimulation during exercise,
FIG. 5 is a graph showing the control of the stimulation voltage when the elbow joint is extended or bent,
FIG. 6 is an explanatory diagram showing a screen displayed on the monitor during exercise.
With reference to FIG. 1 to FIG. 6, taking an example of flexion movement and extension movement of the elbow joint, an explanation of the control of the muscle training device A according to the present embodiment by the computer 4 (see FIG. 3 and FIG. 4). Including.

First, the brace 1 is worn on the upper arms of the left and right arms of the user M (trainer) (FIGS. 1 and 2 show only the state worn on the left arm for convenience).
The brace 1 is worn so that the electrode portion 10 corresponds to the biceps brachii muscle and the electrode portion 11 corresponds to the triceps brachii muscle. For example, when the purpose of exercise is rehabilitation, it can be worn only on the arm on the side where rehabilitation is performed.

  Next, the angle detector 2 is attached to both arms of the user. The upper arm attachment device 21 to which the encoder 20 is attached is attached to the required portion of the upper arm portion by winding the forearm attachment device 22 around the required portion of the forearm portion. At this time, the encoder 20 of the upper arm attachment tool 21 and the wire attachment portion of the forearm attachment tool 22 are positioned on the rear side of the arm. Then, the wire 23 is pulled out from the encoder 20, and the tip portion is attached to the forearm mounting tool 22 (see FIG. 2).

  When the elbow joint is extended or bent in this set state, the wire 23 of the encoder 20 moves in and out with the change in the angle of the elbow joint, and the pull-out amount changes in the forward and reverse directions. As will be described later, the change in the drawing amount of the wire 23 is counted by the controller 3 and sent to the computer 4 as information for calculating the joint angle.

  In addition, the voltage applied to the electrode units 10 and 11 during the elbow joint movement (voltage for each bending angle of the elbow joint) and the time for delaying the timing of voltage application at the start of the exercise (play) are determined in advance for each user. It is set and incorporated in the program stored in the computer 4. Although the example of a setting is shown below, this is an example corresponding to one user and is not limited. Following the setting example for upper arm training (elbow movement), setting example for thigh training (knee movement), lower leg training (ankle movement) A setting example and a setting example for training the trunk are shown.

(A) Upper arm training (movement of the elbow joint)
Direction of movement: Extension → Flexion (Voltage setting for triceps, which is an antagonistic muscle)
・ Elbow joint angle 0 degrees or less:
Output voltage = set voltage x 0.8
・ Elbow joint angle greater than 0 degrees and less than 30 degrees:
Output voltage = set voltage x (0.8 + 0.2 x sin (2 x pi x (elbow joint angle ÷ 360)))
・ Elbow joint angle greater than 30 degrees and less than 50 degrees:
Output voltage = Setting voltage x (0.9 + ((Elbow joint angle-30) / 200))
・ Elbow joint angle greater than 50 degrees and less than 85 degrees:
Output voltage = set voltage-Elbow joint angle greater than 85 degrees:
Output voltage = Setting voltage x (1.0-((Elbow joint angle -85) ÷ 175))

Movement direction: Bending → Extension (Voltage setting for biceps as antagonist)
・ Elbow joint angle 0 degrees or less:
Output voltage = set voltage x 0.9
・ Elbow joint angle greater than 0 degrees and less than 20 degrees:
Output voltage = set voltage x (1.0-((20-elbow joint angle) ÷ 200))
・ Elbow joint angle greater than 20 degrees and less than 60 degrees:
Output voltage = set voltage-Elbow joint angle greater than 60 degrees and less than 75 degrees:
Output voltage = set voltage x (0.9 + ((75-elbow joint angle) / 150))
・ Elbow joint angle greater than 75 degrees and less than 90 degrees:
Output voltage = set voltage x (0.8 + 0.2 x sin (2 x pi x (2 x (90-elbow joint angle) ÷ 360)))
-Elbow joint angle greater than 90 degrees:
Output voltage = set voltage x 0.8

(B) Thigh training (knee joint exercise)
Direction of movement: Extension → Flexion (Voltage setting for quadriceps, internal and lateral vastus muscles that are antagonistic muscles)
・ Knee joint angle 0 degrees or less:
Output voltage = Setting voltage x (1.0-((-Knee joint angle) ÷ 100))
-Knee joint angle greater than 0 degrees and less than 30 degrees:
Output voltage = Setting voltage ・ Knee joint angle 30 degrees or more and less than 50 degrees:
Output voltage = set voltage x (0.9 + ((50-knee joint angle) ÷ 200))
・ Knee joint angle 50 degrees or more and less than 80 degrees:
Output voltage = set voltage x (0.8 + 0.2 x sin (2 x pi x ((80-knee joint angle) ÷ 360)))
・ Knee joint angle 80 degrees or more:
Output voltage = set voltage x 0.8

Movement direction: Flexion → Extension (hamstrings voltage setting as antagonistic muscle)
-Knee joint angle less than 5 degrees:
Output voltage = Setting voltage x (1.0-((5-Knee joint angle) / 125))
・ Knee joint angle 5 degrees or more and less than 40 degrees:
Output voltage = Setting voltage ・ Knee joint angle 40 degrees or more and less than 60 degrees:
Output voltage = set voltage x (0.9 + ((60-knee joint angle) ÷ 200))
・ Knee joint angle 60 degrees or more and less than 80 degrees:
Output voltage = set voltage x (0.8 + 0.2 x sin (2 x pi x ((90-knee joint angle ÷ 360)))
・ Knee joint angle 90 degrees or more:
Output voltage = set voltage x 0.8

(C) Lower leg training (ankle joint exercise)
Movement direction: dorsiflexion → plantar flexion (voltage setting for anterior tibialis anterior muscle, longus extensor muscle)
Same as triceps setting for upper arm training Movement direction: plantar flexion → dorsiflexion (voltage setting for the internal and lateral rectus calf muscles that are antagonistic muscles)
Same as biceps setting for upper arm training

(D) Training of the trunk (exercise of trunk flexion and lateral flexion)
Output voltage = set voltage

After setting the stimulation voltage as described above for each user M, the user M starts exercise.
In the movement of the elbow joint according to the present embodiment, when the arm is bent from the extended state (the movement direction is extended → bent), the extended state of the arm is the initial state. At this time, electricity is not supplied to the electrode portions 10 and 11.

3 and 4 will be mainly referred to.
(1) When the user M moves the forearm from the initial state and the elbow joint begins to bend, the wire 23 of the encoder 20 is pulled out, whereby the counter unit 34 of the controller 3 counts the pull-out amount. Is sent as information to the computer 4 wirelessly.

(2) The count value acquired by the computer 4 is divided for each encoder 20, and based on the count value corresponding to each encoder 20, the calculation unit 46 calculates the joint angle, the movement direction, and the encoder part. The The movement state is confirmed and evaluated from the calculation result of the movement direction (movement evaluation will be described later). Further, the stimulation part is determined from the calculation result of the movement direction and the encoder part.

(3) If the exercise state is appropriate, the exercise state is confirmed by comparing the count value with the value one loop before (the latest acquired by the computer). In addition, when a motion state is not appropriate, for example, a minute bending / extending motion of the joint is performed, the mode is switched to a safe mode (a mode in which the maximum applied voltage is reduced by 20%) (FIG. 4, step S1).
If the change amount of the count value is smaller than the set value, electrical stimulation is not performed. Further, if the amount of change in the count value is larger than the set value, a region for performing electrical stimulation by determining the direction of movement (the triceps surae) is determined, and each joint angle is determined based on the set value. Each stimulation voltage and rise time (omitted in the setting example) are determined (FIG. 4, step S2).

(4) Further, the evaluation of the motion state is performed by comparing the calculated value of the joint angle with a value (ideal value) set in advance as an example (FIG. 4, step S3). This evaluation is displayed on the screen of the monitor 40 as an angle evaluation graph 44 and an exercise evaluation graph 45. In addition, an image of the model 43 representing the user's movement is also calculated in real time based on the calculated value of the joint angle and displayed on the screen of the monitor 40 (see FIG. 6). Note that the movement of the model 42 that performs an exemplary movement is made based on the ideal value.

  In this way, by displaying the virtual image on the monitor 40, the user can visually check the evaluation and achievement status of the exercise task, and whether or not the exercise has been appropriately performed, etc. It is possible to provide feedback. That is, it has a feature as a virtual reality device capable of bidirectional information exchange. Furthermore, it is possible to expect to maintain or improve motivation for exercise by providing entertainment to the exercise and feeling a sense of accomplishment.

  Furthermore, the user not only can exercise while visually confirming whether he / she is performing sufficient bending / extension exercise, but also performs self-evaluation of the exercise after exercise with reference to the image displayed on the monitor 40. Can do. In this apparatus, since the information of the encoder 20 can be acquired not only as the expansion / contraction direction but also as the joint angle, the user's bending / stretching state can be grasped, and the information can be fed back on the screen of the monitor 40.

  In addition, by displaying an angle evaluation graph 44 in which the graph bar expands and contracts according to the joint angle and the color tone changes on both sides of the screen, it is possible to easily grasp whether the current bending state is sufficient. Yes, the exercise evaluation graph 45 also displays the achievement rate of the exercise, etc., and thereby can encourage the user to bend and extend sufficiently. It should be noted that different chimes may be sounded when the user is able to bend and stretch enough so that the user can grasp the state by sound.

  Moreover, the recording of these joint movements and the recording of the movement state incorporates a mechanism that is recorded together with the applied voltage, and can be referred to after the movement, thereby enabling detailed evaluation of the movement state. With these mechanisms, the user can exercise while visually confirming whether or not he / she is sufficiently bending / extending, and can also evaluate the exercise state after the exercise.

(5) When the stimulation voltage and the stimulation site are determined, the control command is wirelessly sent to the controller 3, and the power supply unit (electric stimulation generation block) 30 to the electrode unit 11 (electrode 10 in the case of extension movement) On the other hand, a controlled voltage is applied, and electrical stimulation is applied to the triceps surae muscle, which is an antagonistic muscle during flexion movement, causing muscle contraction. Thereby, the exercise | movement resistance by a triceps triceps contracting can be provided with respect to the exercise | movement of the biceps, which are main muscles.

(6) When the bending movement of the arm reaches the end of the movement, the extension movement in the reverse direction is performed. At the end of exercise, electrical stimulation to the triceps muscle during exercise stops. When the extension exercise is started, electrical stimulation is performed on the biceps brachii muscle, which is an antagonistic muscle of the extension exercise, by the control similar to the above by the controller 3 and the computer 4 (the set value of the stimulation voltage is different).

With reference to FIG. 5, an example of stimulation voltage control when the elbow joint is extended or bent will be described.
This exercise is performed alternately on the left and right. That is, during one extension movement, the other bending movement is performed in parallel.

(Exercise direction: extension → flexion, antagonistic muscle: triceps)
Elbow joint angle 0 degrees ↓ Delay the timing of voltage application at the beginning of exercise (play).
↓ Applied voltage 0V → 25V
Elbow joint angle 5 degrees ... Applied voltage 25V
↓ Increase the applied voltage step by step based on the setting for each joint angle.
↓ Applied voltage 25V → 31V
Elbow joint angle 56 degrees ... Applied voltage 31V
↓ Maintain at the maximum value of 31V Elbow joint angle 86 degrees ... Applied voltage 31V
↓ Decrease the applied voltage.
Elbow joint angle 89 degrees ... Applied voltage 30V
↓ Decrease the applied voltage rapidly.
Elbow joint angle 90 degrees ... Applied voltage 0V
Turn over the elbow joint movement and move on to the extension movement.
(Exercise direction: Flexion → Extension, Antagonist muscle: Biceps)
Elbow joint angle 90 degrees ... Applied voltage 0V
↓ Applied voltage 0V → 20V
Elbow joint angle 89 degrees ... Applied voltage 20V
↓ Increase the applied voltage step by step based on the setting for each joint angle.
↓ Applied voltage 20V → 25V
Elbow joint angle 46 degrees ... Applied voltage 25V
↓ Maintain at the maximum value of 25V.
Elbow joint angle 2 degrees ... Applied voltage 25V
↓ Decrease the applied voltage.
Elbow joint angle 1 degree ... Applied voltage 24V
↓ Decrease the applied voltage rapidly.
Elbow joint angle 0 degrees ... Applied voltage 0V
Turn the elbow joint motion back to flexion.

Note that the muscle training device A according to the present embodiment has a simple configuration in which electricity is supplied only to muscles that are antagonistic muscles in the upper arm, but the invention is not limited to this, and the main movement during exercise is not limited to this. It is also possible to apply electrical stimulation to muscles to be muscles and to provide orthoses at a plurality of locations. In this way, it is possible to cope with complicated movements of parts other than the joints.
In this embodiment, the intensity of the electrical stimulation is controlled by controlling the voltage to be applied. However, the present invention is not limited to this, and can be performed by controlling the current.

  The terms and expressions used in the present specification are merely explanatory and not restrictive, and do not exclude terms and expressions equivalent to the above terms and expressions. The present invention is not limited to the illustrated embodiment, and various modifications can be made within the scope of the technical idea.

Schematic explanatory drawing of the muscle training apparatus which concerns on this invention. Explanatory drawing which shows the mounting state of an angle detector. The flowchart from the detection of the joint angle at the time of exercise to electrical stimulation. The flowchart which shows control of the electrical stimulation at the time of exercise | movement. The graph showing the control of the stimulation voltage at the time of extending or bending the elbow joint. Explanatory drawing which shows the screen displayed on a monitor at the time of exercise.

Explanation of symbols

A muscle training device 1 orthosis 10 and 11 electrode 2 angle detector 20 encoder 21 upper arm attachment 22 forearm attachment 23 wire 3 controller 30 power supply unit 31 communication unit 32 cable 33 cable 34 counter unit 4 computer 40 monitor 41 communication Unit 42 Model 43 Model 44 Angle evaluation graph 45 Motion evaluation graph 46 Calculation unit

Claims (6)

In a movement that flexes or extends a joint by a closed movement chain that applies electrical stimulation to the muscle that becomes the antagonistic muscle and performs centrifugal contraction when the muscle that becomes the main muscle is contracting,
Based on information on joint angles that change with exercise, within the predetermined range of electrical stimulation that the user can withstand, the muscles of the main muscle during exercise are contracted against antagonistic muscles at the beginning of exercise. Give the antagonistic muscle an electrical stimulus that produces a contraction force that is sufficiently smaller than the force, and gradually increase the strength of the electrical stimulus toward the end of exercise, or For each angle, an electrical stimulation of a strength that gives a suitable muscle contraction to the antagonistic muscle is determined in advance.
Electrical stimulation of muscles. A muscle training device that can train the main and antagonist muscles in parallel by applying electrical stimulation to the antagonist muscles when the antagonist muscles are stretched by contracting the main muscles,
An orthosis (1) having an electrical stimulation unit (10, 11) for applying electrical stimulation to muscles;
Angle detection means (2, 20, 21, 22) for detecting the angle of the joint that performs extension or bending movement;
An electricity supply unit (3, 30) for supplying electricity to the electrical stimulation unit (10, 11);
A computer (4) for controlling the electricity supply unit (3, 30);
With
The computer (4)
Based on the information for calculating the angle of the joint that changes with movement, detected by the angle detection means (2, 20, 21, 22), the strength of the predetermined electrical stimulus that the user can withstand Within the range of the above, for the antagonistic muscle, in the initial stage of exercise, the electrical stimulation part (10, 11) causes the antagonistic muscle to generate a contraction force sufficiently smaller than the contraction force of the main muscle during exercise. And a program that controls to gradually increase the intensity of electrical stimulation toward the end of exercise,
Muscle training device. A muscle training device that can train the main and antagonist muscles in parallel by applying electrical stimulation to the antagonist muscles when the antagonist muscles are stretched by contracting the main muscles,
An orthosis (1) having an electrical stimulation unit (10, 11) for applying electrical stimulation to muscles;
Angle detection means (2, 20, 21, 22) for detecting the angle of the joint that performs extension or bending movement;
An electricity supply unit (3, 30) for supplying electricity to the electrical stimulation unit (10, 11);
A computer (4) for controlling the electricity supply unit (3, 30);
With
The computer (4)
Based on the information for calculating the angle of the joint that changes with movement, detected by the angle detection means (2, 20, 21, 22), the strength of the predetermined electrical stimulus that the user can withstand Within the range of the above, for the antagonistic muscle, in the initial stage of exercise, the electrical stimulation part (10, 11) causes the antagonistic muscle to generate a contraction force sufficiently smaller than the contraction force of the main muscle during exercise. And a program for controlling the antagonistic muscle to give an electrical stimulus having a strength that can provide a suitable muscle contraction, which is predetermined for each joint angle toward the end of movement.
Muscle training device. When an unstable movement occurs in the movement of the user in the computer (4), the movement is sensed based on the information acquired by the angle detection means, and the electric stimulation unit (10, 11) With a program that controls to reduce the intensity of stimulation or to stop electrical stimulation,
The muscle training apparatus in any one of Claim 2 or 3. A monitor (40) is provided, and the computer (4) displays an image of the model (42) that performs an exemplary movement of the movement performed by the user on the monitor (40), and the angle according to the movement of the user. Based on information acquired by the detection means (2, 20, 21, 22), an evaluation for the movement of the model (42) is calculated, and a program for displaying the evaluation on the monitor (40) is provided.
The muscle training apparatus in any one of Claim 2, 3 or 4. A monitor (40) is provided, and the computer (4) calculates the movement of the user based on information acquired by the angle detection means (2, 20, 21, 22) along with the movement of the user, A program for displaying movement on the monitor (40) as an image of the model (43) is provided.
The muscle training device according to any one of claims 2, 3, 4, and 5.