# US 11,298,589 B2 · Foot training device and foot training method

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- Number: US 11,298,589 B2
- Document ID: US11298589B2
- Status: Granted
- Kind: B2
- Application number: 17/048,229
- Filed: 2020-03-04
- Published: 2021-08-05
- Granted: 2022-04-12
- Earliest claimed: 2019-04-24
- Assignees: Nasyu Co., Ltd.
- Applicants: Nasyu Co., Ltd.
- Inventors: Tomokazu Nasu; Keiichi Sakai; Naoji Sakai
- Web page: https://patentgrep.com/patent/US11298589B2

## CPC

- A63B 21/0455: {having torsion element around its longitudinal axis}
- A63B 23/10: for feet or toes
- A61F 5/019: {Toe correcting or spreading devices}
- A61H 1/0266: {Foot}
- A63B 21/00058: {Mechanical means for varying the resistance (A63B21/06 takes precedence)}
- A63B 21/00061: {Replaceable resistance units of different strengths, e.g. for swapping}
- A63B 21/025: {Spiral springs with turns lying substantially in plane surfaces}
- A63B 21/028: {made of material having high internal friction, e.g. rubber, steel wool, intended to be compressed (resistance provided by plastic deformable materials A63B21/00189)}
- A63B 21/045: having torsion {or bending or flexion} element
- A61H 2001/027: {Toes}
- A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H)
- A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C)
- A61H: PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY (electrotherapy, magnetotherapy, radiation therapy or ultrasound therapy A61N)

## Abstract

A training device is provided for training a foot using the device. The training device includes a fulcrum placed at a center and four projections that project in different directions from the fulcrum. Each of the four projections have elastic members that are bendable. The training device is configured to improve foot muscle strength by bending and stretching the elastic members. At least two of the four projections have different degrees of elasticity in flexure as determined when a force is applied to a distal end of each of the at least two projections to bend the elastic members. The four projections project in cross directions from the fulcrum at the center. Each pair of projections that oppose each other across the fulcrum are arranged on a straight line.

## Claims

### Claim 1

A foot training device comprising:
a fulcrum placed at a center; and
four projections projecting in different directions from the fulcrum, each of the four projections having, at least in a portion of each of the four projections, an elastic member that is bendable in a bending direction, wherein:
the training device is configured to be used to improve foot muscle strength by bending and stretching one or more of the elastic members, and at least two of the four projections have different degrees of elasticity in flexure as determined when a force is applied to a distal end of each of the at least two projections to bend the elastic member,
the four projections project in cross directions from the fulcrum at the center, and, for each pair of projections that oppose each other across the fulcrum, the projections are arranged on a straight line,
none of the four projections has an annular structure, and
all of the four projections have different lengths.

### Claim 2 (depends on 1)

A foot training method comprising the steps of:
placing the foot training device according to claim 1 on a floor surface;
bringing a heel of a foot into contact with the foot training device;
hooking a toe around an end edge of the distal end of at least one of the projections;
pulling up the distal end of the projection in this state; and
bending and stretching the projection using muscles of a sole, thereby improving muscle strength of the sole.

### Claim 3 (depends on 1)

A foot training method comprising the steps of:
holding one of the projections of the foot training device according to claim 1 between two adjacent toes of a foot;
bringing a heel of the foot into contact with the training device;
pulling up the projection in this state; and
bending and stretching the projection using muscles of a sole, thereby improving muscle strength of the sole.

### Claim 4

A foot training device comprising:
a fulcrum placed at a center;
four projections projecting in different directions from the fulcrum, each of the four projections having, at least in a portion thereof, an elastic member that is bendable in a bending direction; and
an elastic body layer and two protective layers that are stacked together, the elastic body layer being made of a plate-shaped resin material or rubber material, the two protective layers being made of a resin material or a rubber material having a lower elastic modulus than the elastic body layer and a higher foaming ratio than the elastic body layer, and the two protective layers being provided on two plate surfaces of the elastic member, respectively, wherein:
the training device is configured to be used to improve foot muscle strength by bending and stretching one or more of the elastic members, at least two of the four projections have different degrees of elasticity in flexure as determined when a force is applied to a distal end of each of the at least two projections to bend the elastic member,
the four projections project in cross directions from the fulcrum at the center, and, for each pair of projections that oppose each other across the fulcrum, the projections are arranged on a straight line, and
none of the four projections has an annular structure.

### Claim 5 (depends on 4)

A foot training method comprising the steps of:
placing the foot training device according to claim 4 on a floor surface;
bringing a heel of a foot into contact with the foot training device;
hooking a toe around an end edge of the distal end of at least one of the projections;
pulling up the distal end of the projection in this state; and
bending and stretching the projection using muscles of a sole, thereby improving muscle strength of the sole.

### Claim 6 (depends on 4)

A foot training method comprising the steps of:
holding one of the projections of the foot training device according to claim 4 between two adjacent toes of a foot;
bringing a heel of the foot into contact with the training device;
pulling up the projection in this state; and
bending and stretching the projection using muscles of a sole, thereby improving muscle strength of the sole.