Martial artists use board breaking as a method to demonstrate various attributes such as proper technique, power, targeting and speed among others. Board breaking is used in rank advancement testing, competitions, and even setting Guinness™ world records. Breaking boards requires one or more fellow students to hold the board (referred to as “holders”) for the student performing the technique (referred to as a “breaker”). While hand techniques are usually very accurate, foot techniques used in board breaking are usually not very accurate. High speed breaking techniques, particularly kicks, can cause noticeable injury to the hands and fingers of the holder(s) due to poor targeting by the breaker. Once struck/injured, a holder is likely to “flinch” or move the board/target on subsequent attempts, increasing the difficulty of successfully breaking the board/target.
Prior art attempts at providing some hand protection have been generally unsuccessful, for example, benefitting only the holder, or compromising between benefitting the breaker and benefitting the holder to the point that neither attempt at protection has worked. A prior art attempt at providing hand protection is illustrated by the sheath (12) in U.S. Pat. No. 4,807,302 by Cannella. A prior art product very similar to the disclosure of Cannella, and marked in the past with the Cannella patent number, has been and is commercially available, but it does not include the spikes 14 shown in the Cannella drawings. Other prior art attempts at hand protection include the holder(s) wearing of padded gloves.
Increased Chance of Injury:
The inventors believe, in order to avoid or minimize the chance of injury, a holder should hold a board/target with the hand and fingers generally in the position shown by the bare-hand portrayal in FIG. 1A. This places the metacarpophalangeal joints (“knuckles” K) directly adjacent to (directly above in the drawing) the edge of the board B and at or very close to the central plane CP of the board. Further, the inventors prefer that the hand and forearm lie in positions wherein the heel H of the palm is slightly distanced from the board (see P1) and closer to the outer perimeter region E of the board, rather than being closer to the central region CB of the board, which is understood to be below FIG. 1A. Note the curved dashed line in FIG. 1A that indicates that many martial arts boards have a non-planar rear surface, due to the outer perimeter regions being the thickest portion of the board and the central region CB being of lesser thickness and/or having break joints. The front surface of a martial arts board is typically planar, represented by the front plane FP in FIG. 1A, and the outer perimeter edge surface ES is typically planar and perpendicular to the front surface and front plane FP.
These preferred hand and forearm positions may be described as the hand/wrist being rotated into the position in FIG. 1A from the position of FIG. 1B, which for these figures is a counterclockwise rotation. Note that, in FIG. 1B, the knuckles K are behind the central plane and the rear surface of the board, and the heel H of the palm is pressed against the board and closer to the center region CB of the board.
The preferred position results in an angle between the main portion of the hand (and/or the palm) and the forearm is a large obtuse angle O1 and small supplementary angle A1. The inventors prefer an angle O1 of greater than or equal to 135 degrees and a corresponding supplementary angle A1 of equal to or less than 45 degrees. Possible ranges for the obtuse angle O1 may be, for example, 135-160 degrees, or especially about 135-155 degrees. Possible ranges for the acute angle A1 may be, for example, 45-20 degrees, or especially 45-25 degrees.
The Cannella sheath CAN-S and said prior art commercial product COMM, on the other hand, are adapted to hold the fingers, hand, and wrist in positions substantially similar to those portrayed by the bare-hand holding the board in FIG. 1B. When the Cannella CAN-S and commercial product COMM are used, as shown in FIGS. 2A and 3A, respectively, the fingers, hand, and wrist positions stay similar to those in FIG. 1B. FIGS. 2A and 3A show that the fingers inside the Cannella/commercial-product, up to about the proximal inter-phalangeal joint (that is, the distal phalanx and the middle phalanx), lie parallel to and close to the front plane FP and the central plane CP of the board/target.
When inside the Canella sheath CAN-S, as shown by FIG. 2A, the fingers' distal phalanx and the middle phalanx are parallel to the board, distanced evenly all along their lengths from the front surface of the board by spikes (“14” in Cannella) and by the thickness of the underside (“18” in Cannella) of the sheath. Note, too, in FIG. 2A, that the metacarpophalangeal joints (knuckles K) lie rearward of the central plane CP of the board. The palm lies tight against the rear surface of the board (see P2) and the wrist W is closer to the center region of the board than in FIG. 1A. The angle O2 of the forearm to the palm is smaller than angle O1, for example, less than 135 degrees, and more typically in the range of about 110-134 degrees. The corresponding supplementary angle A2 in the Canella sheath, therefore, is greater than 45 degrees, and more typically in the range of about 70-46 degrees. Note that the board outer perimeter region E region, which is typically the thickest region of a martial arts target board, is shown with front and rear surfaces parallel to each other, but the board may have a reduced thickness and/or curved rear surface nearer to the center of the board as shown by the curved line C.
The commercial product is likewise adapted so that the fingers, up to about the proximal inter-phalangeal joint (especially the distal phalanx and the middle phalanx), lie parallel to the front plane and the central plane of the board/target. In the commercial product COMM, as shown by FIG. 3A, the fingers' distal phalanx and middle phalanx are parallel to the board, distanced evenly from the front surface of the board, only by the thickness of the underside of the sheath. Note in FIG. 3A that the metacarpophalangeal joints (knuckles K) lie rearward of the central plane CP of the board. The palm lies tight against the rear surface of the board (see P3) and the angle of the forearm to the palm O3 and the supplementary angle A3 are the same or nearly the same as O2 and A2 of the sheath of the Cannella patent, described above.
In summary, the surface that the user's fingers rest on, inside these prior devices, is parallel to the board, requiring the holder's fingers distal and middle phalanx to lie flat/parallel relative to the board's front and central planes, and forcing the heel of the holder's palm toward the board and further in toward the center of the target. These features of the prior art devices increases the likelihood of “jamming” the holder's wrist(s) as a result of a kick/strike.
Further, the Cannella sheath is described as “made of a tough, substantially nondeformable, abrasion and cutting resistant material, such as plastic or metal”. The prior art commercial product related to Cannella is advertised as being made of Lexan™ polycarbonate, which the inventors note is hard, rigid, and completely-inflexible, and tends to become brittle over time making it more susceptible to breaking/shattering when struck. Also, as shown to best advantage in FIGS. 2B and 3B, both the Canella sheath and the commercial product comprise a flange FL (reference 28 in Cannella) that protrudes rearward from the sheath. This flange FL extends along, and typically rests against, the outer perimeter edge surface ES of the board to control and limit the position of the sheath on the board. Thus, the flange FL extends behind the front plane FP of the board and does not contact the front surface of the board. This flange FL is believed by the inventors not only to limit the user's options for hand placement when holding the board, but also to increase the likelihood of breaker injury due to the introduction of rigid surfaces/edges into the target area.
Inadequate Gripping Surface:
Padded gloves commonly available in martial arts circles may protect the holder's fingers to some extent, and may provide a cushioned surface should the breaker hit the glove. However, even conventionally-padded, prior art martial arts gloves decrease the holder's grip, resulting in the target acting “slippery” and being difficult to hang on to. Gloves with increased padding would only interfere further with the holder's grip on the board. The result of padded gloves, therefore, is typically a reduced grip on the target, increasing the likelihood of dropping or prematurely releasing the board/target during the attempt and resulting in a missed attempt on the break.
Therefore, there is still a need for an improved device for finger protection in martial arts, and embodiments of the invention meet this need. Certain embodiments of the invention provide correct ergonomic positioning that is very different from the positioning encouraged by prior art sheaths. Also, certain embodiments of the invention provide the holder with multiple options for hand and protector placement on the board, while also providing a sure grip. Also, certain embodiments comprise firm, but non-injuring and slightly-compressible, elements and surfaces that provide a surprisingly-effective balance of protecting/shielding the holder's hand/fingers and protecting the striker's foot and toes in the case of striking with the foot, or hands and fingers in the case of striking with the hand.