Сила хвата: типы, факторы и применение.

Force applied by the hand to hold

Grip strength is the force applied by the hand to pull on or suspend from objects and is a specific part of hand strength. Optimum sized objects permit the hand to wrap around a cylindrical shape with a diameter from one to three inches. Stair rails are an example of where shape and diameter are critical for proper grip in case of a fall. Other grip strengths that have been studied are the hammer and other hand tools. In applications of grip strength, the wrist must be in a neutral position to avoid developing cumulative trauma disorders. Grip strength is a general term also used to refer to the physical strength of an animal and, for athletes, to the muscular power and force that can be generated with the hands. In athletics, grip strength is critical for rock climbers and is an important factor in strongman competitions and weight lifting. Grip strength training is also a major feature in martial arts and can be useful in various professions where people must work with their hands.

The human hand can be used to grip objects in several different positions. These different positions require different types of grip strength which are typically quantified based on the way the hand is being used. The crush grip is what is most commonly thought of as "grip". It involves a handshake type grip, where the object being gripped rests firmly against the palm and all fingers. A strong crush grip is useful in bone crushing handshakes, or for breaking objects with pressure. In a pinch grip, the fingers are on one side of an object, and the thumb is on the other. Typically, an object lifted in a pinch grip does not touch the palm. This is generally considered a weaker grip position. The pinch grip is used when grabbing something like a weight plate or lifting a sheet of plywood by the top edge. A support grip typically involves holding something, such as the handle of a bucket, for a long time. This type of strength is epitomized by the Farmer's walk competitive event, where the bucket is filled with sand or water, and carried over a long distance. A great deal of muscular endurance is necessary to have a good carrying grip.

There has been extensive medical and ergonomic research looking at grip strength, which has found that 95% of men have a grip strength greater than 90% of women. Averages also exist for different types of grip in different positions. Grip strength increases or decreases depending on the arm position at which the grip strength is being measured. A person's grip strength usually results in having the strongest grip strength when their arm is extended at 90° before their body, as opposed to the other extreme arm positions, rested at one's side or held straight up above one's head. Grip strength is not optimal if one's arm is extended backwards beyond the resting position at the body's sides. It can be concluded that grip strength is affected via the different arm muscles and their ability to contract.

Grip strength training requires a different type of training regimen than other muscular training. The reasons are primarily based on the interplay of the tendons and muscles and the lack of "down time" or rest that most people's hands get. It is generally considered that all aspects of the hand must be exercised to produce a healthy and strong hand. Only working on closing grip will cause an imbalance between closing and opening (antagonist) muscles, and can lead to problems such as tendinitis and carpal tunnel syndrome.

Thick bar and Thick Grip work on a two inch or thicker bar—such as deadlifts, pullups, and the farmers walk—trains the support grip. Grippers train the crushing grip. Plate pinches Place the weight plate on the ground standing upright on its side. Bend down and hold the plate using a pinch grip between your fingers and thumbs only. The plate shouldn't touch the palm of your hand. Straighten up and lift the plate using the pinch grip, up to your chest, and then slowly place it back on the ground. Sledgehammer lever — levering a sledgehammer using the wrists to train fingers and wrists. Plate curls/wrist curls — grabbing a plate and doing wrist curls or regular curls with them with the fingers on the bottom and thumb on top, trains the wrists and fingers and thumb for pinch grip. Blockweights — cut off ends of hex dumbbells that are grasped in a pinch grip fashion from different sides of the blockweight with one end grasped by fingers and other by thumb; trained with either singles, timed holds, or tosses from hand to hand. Hangboard can be used for training the full crimp grip, half crimp grip and open hand grip, required in climbing. Short steel bending works the "closing grip" in a unique way. It combines a cylindrical gripping motion of the steel bar with the ulnar deviation of the wrist. This action is then forced into an isometric "hold" of sorts, as the bender attempts to bend the bar using only their two hands.

Extensors; these are the muscles that oppose the flexors of the hands and should be trained to achieve a good balance between opposing muscle groups; extensor muscles are key in grip because they must contract aggressively to support finger flexion. Shoving your hand in something like rice and extending it, or placing something such as rocks in a coffee can, putting your hand in there, and extending it to pick up the coffee can, are ways of training your hand extensors. Some grip companies sell high resistance rubber bands which work the extensor grip. Another option, is a weight based machine; this type of plate loaded machine will not only strengthen your grip but also your forearm strength. As finger flexor/extensors serve a function as wrist flexor/extensors, doing wrist extension exercises (sometimes called "reverse wrist curls") would also stimulate the finger extensor fibers. Doing fist pushups on the backside of the first finger bone would increasingly put pressure on the extensor muscles as weight was shifted from knuckle end to the further joint. When in a tight fist, the flat of the fingernails can dig into the palm and push the skin down to create a bridge to stabilize the first structure and prevent hyper flexion of the knuckle joints (which can be observed by doing pushups with the entire backside of the fingers flat on the ground, fingers pointing towards the opposite hand).

Fingertip pushups would utilize both opening and closing grip muscles to keep the finger from sliding, as well as more focused bone density in the hand, though they are very strenuous and dangerous unless approached progressively. Handstands free from a wall with fingers pointing behind would use gripping stretching to stabilize the hand to prevent the body from falling towards the front, and extensor muscles to prevent the body from falling towards the back. Metal rod exercises strengthen the grip indirectly but very effectively through strength training using a metal rod or pole.