The Boxing Cross - Mr Fortier's Web of Fun



The Boxing Cross (Punch)

By Chris Crawford

[pic]

Starting position

[pic]

Regular Stance

In boxing, a cross is a straight punch delivered from the right hand in regular stance, and the left hand in southpaw (left-handed) stance. For the sake of simplicity, this report will describe the movements of a right-cross made by a boxer starting in regular stance; with the left leg leading and both feet pointed at an angle of about 45 degrees away from the opponent. Both elbows are bend with the right hand behind the left as both hands are held at or just below mouth level and both knees slightly bent. In stance, the trunk and shoulders should start off in a position where they are facing the same direction as the feet. Weight is placed fairly equally between feet, as the stance serves as a defensive position as well as an offensive one.

Joints Involved

The cross involves the movement of 3 major joints, and many more joints in the wrist and hand, which must be stabilized upon impact with the opponent. The joints that move the most are the elbow, shoulders and trunk, while lower body joints such as the ankles and knees also move to accommodate the weight transfer used to create a powerful punch.

[pic][pic]

The Trunk

In the right cross, the trunk is the first thing to move. It rotates along the polar axis, through the transverse plane. Sometimes to get even more power, the boxer may rotate the hips rather than the actual trunk, pointing the front of the pelvis directly towards the opponent. This motion would also occur on the polar axis through the transverse plane.

Shoulders

In starting stance, the shoulders are usually slightly flexed, somewhat perpendicular to the floor because the back is hunched over as well. Also, the arms may be slightly abducted from the body. When the punching motion begins, the arm is brought posteriorly to the point that the elbow may be behind the shoulder joint in order to create more power. When this motion is made the arm also abducts even more, as the hand pronates in preparation for the strike. When the forward motion of the punch begins, the humerus may be abducted to the point that it is parallel with the clavicle. The shoulder then rotates along the polar axis as the humerus moves through the transverse plane, until the shoulder is in a flexed position, with the right arm straight out anterior to the rest of the body. It is also important to note that the scapula protracts during the punching motion to provide extra reach and power to the punch.

Elbows

The elbows start of in a flexed position. As the arm is brought posteriorly to gather power for the punch, the right elbow is flexed even more. As arm begins to move anteriorly, the elbow begins to extend until it hits the opponent. Ideally, the elbow should snap into full extension just as the boxing glove hits the opponent, or else earlier to avoid injury to the elbow joint from hyperextension. Because the arm is abducted during the punching motion, most of the elbow flexion and extension that occurs takes place on the polar axis, through the transverse plane.

Muscles Involved

The main muscles used in the right cross are the pectoralis major, anterior, lateral and posterior deltoids, triceps brachii, serratus anterior, external obliques, rectus abdominus, wrist flexors & extensors as well as some lower body muscles such as gastrocnemeus and the quadriceps group which may be used to provide extra power.

Pectoralis Major

As the shoulder joint rotates the humerus along the polar axis, the contractions that cause the movement are made by either the pectoralis major or the posterior deltoid. The pectoralis major is able to generate a large amount of power that goes towards the punch, as it contracts concentrically to bring the right shoulder and arm forward.

Deltoids

The anterior deltoid assists the pectoralis major in drawing the arm forwards during the punching motion, contracting concentrically. Both the anterior and lateral deltoids stabilize the humerus upon contact with the opponent. The lateral deltoid is responsible for the abduction of the humerus to raise the arm into a position where the arm is “cocked” for the punch. The posterior deltoid also contracts concentrically to assist in this motion, pulling the arm back to prepare for the punch. The posterior deltoid also works to balance the shoulder joint during the punch where the pectoralis major and anterior deltoid are contracting to exert punching force.

Triceps Brachii

The triceps brachii create most of the power used in the extension of the elbow joint. The contract concentrically during the punching motion, while the arm and shoulder are being drawn forward towards the opponent.

Rectus Abdominus and External Obliques

The rectus abdominus and external obliques generate much of the power that is created through the rotation of the trunk and also help to stabilize and keep balance by contracting isometrically, especially if the boxer leans forward to land the punch. The external obliques provide power for the twisting motion as the upper body rotates to bring the punching arm towards the opponent.

Serratus Anterior

The serratus anterior provides additional power to the final part of the motion. As the elbow becomes fully extended and the arm is almost straight, the serratus anterior contracts concentrically to protract the scapula and move the entire shoulder joint anteriorly, ending the punching motion with one last push.

Wrist Flexors & Extensors

Wrist flexors and extensors also contract isometrically in order to transfer the maximal force of the punch through the arm into the opponent. If the wrists are not kept straight, the force of the punch is lessened, and the potential for injury increases as well.

Possible Injuries

Upon contact with the opponent, force is exerted on impact through the right arm to the shoulder and through the body.

Wrists and Fingers

The first joints to receive the impact of a landed punch are the fingers, metacarpals, carpals and the wrist joint. The many small bones in the hand are susceptible to fractures, and the tearing of the small ligaments that hold them together. Commonly, boxers break the 4th and 5th metacarpals, which are known as “Boxer’s fractures”. The wrist may be sprained during competition or training, and in most severe incidents the ligaments that hold the bones of the wrist joint together may be torn to the point that the bones are moved out of place, into partial dislocation. If the boxer does not have some sort of support for their wrists, and they may not have strong enough wrist flexors and extensors they are more likely to injure the joint or muscles that extend the wrist. Most boxers use tape or wrap to support their wrists.

Elbow

If the elbow is fully extended upon impact with the opponent, there is the risk of hyperextension if the muscles antagonistic to the triceps brachii (the biceps brachii, brachialis etc.) are not able to balance the force applied by the triceps. Since the cross is not a completely straight punch, the elbow may hyperextend, causing damage to the ligaments of the elbow joint.

Shoulder

When the punch hits the opponent or training bag, the muscles are susceptible to tears because of the rapid deceleration caused by the impact. The shoulder joint may slow down slower than the arm does, which can result in an injury to the rotator cuff. Repeated punching may also cause tendonitis and even dislocation of the shoulder joint.

Treatment and Prevention

If an athlete fractures one of the many small bones in their hand, they will need to see a doctor to have the bones set and a cast applied and rest the injury for at least 8 weeks. In more severe incidents, the boxer may crush multiple bones in the hand, which could require surgery and an even longer resting period. Injuries to the wrist such as sprains can be treated with by following the R.I.C.E. method and rested for about 3 weeks, although in some cases a splint may be needed to provide stability for the joint. If the wrist becomes dislocated surgery may be required to repair torn ligaments. To prevent future wrist and hand injuries from occurring, proper taping should be applied to both hands to secure and support the joints.

Elbow hyperextension is a somewhat rare injury, but can cause severe pain and discomfort for the athlete. Depending on the severity, treatment can range from resting and icing the joint to the possibility of surgery.

Injuries to the rotator cuff muscles, depending on the severity of the tear, may require resting, icing and rehabilitation before the athlete is ready to box again. The same rule applies to a dislocated shoulder caused by the punch, however if many of the ligaments of the shoulder joint are completely or mostly torn surgery is the most likely solution. Following surgery, rehabilitation is required to improve the strength and flexibility of the joint. The best way to avoid shoulder injuries in boxing is to practice proper training techniques, keeping muscle strength balanced and getting the muscles used to the repeated punching.

I hope that this information has been useful in developing any equipment that may help to prevent injuries that an athlete may sustain while performing a cross punch in boxing. Often the injuries caused to the joints of athletes through performing a punch are overlooked because of the high impact nature of boxing, as professional boxers are known to experience head and spinal injuries very often from taking so many punches. I hope that this information will be helpful in improving the quality and technology of the equipment.

References

Exercise Science textbook







................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download