Always punch with a tightly closed fist, and make sure your thumb is tucked over your middle knuckles. If you wrap your fist over it or allow it to protrude, you risk breaking it should you actually hit something. The back of your hand should be roughly aligned with your forearm, rather than bent; the striking surface is the knuckles of your pinky, ring finger and middle finger. Generally, your fist should be horizontal for jabs and crosses, but turned with the thumb slightly down for hooks. Some martial art styles advocate a vertically aligned fist, however, it takes practice to learn to do this effectively. Strike anywhere below the forehead and always aim several inches behind your actual target. Any boxing coach will tell you to throw punches in bunches, and you would be wise to heed this advice. Multiple, quick shots are much harder to see, with one shot hiding the next, and the chances of scoring a one hit knockout are fairly slim. It's also much harder to block if you throw multi-hit combos, alternating between body and head. This is where conditioning comes into play. A less skilled, but better conditioned fighter can simply smother a more skilled, yet less conditioned fighter with a huge punch output.
The Jab: From fighting stance, the jab is executed with the forward arm. Punch straight out without drawing it back in preparation or allowing your elbow to pull away from your body horizontally. Twist your shoulders and hips slightly to give power to the punch; it is OK to pivot or step forward slightly on your front foot. Draw the fist back to its original position. The jab is a quick punch that is often used by itself, or in combination with the more powerful cross. The jab can also be used to determine the distance between you and your opponent, as it can be flicked out quickly without exposing yourself.
The Straight: The straight is executed with the rear hand; punch straight out without allowing your elbow to pull away from your body horizontally, pivoting the shoulders and hips to give maximum power. As the arm extends, twist the heel of your back leg outward by rotating on the ball of your foot to give the punch more power, but be careful to not throw yourself off-balance. The straight is a very powerful punch, and should be a bread and butter shot. It has range, power and reasonable speed. The 1-2 (Jab-Straight combo) is a basic, but very effective boxing technique and should be practiced until it is second nature.
The Cross:The cross is similar to the straight, however the punch is arced slightly to come at the opponent from above. It is almost always thrown as a counter punch, with your arm almost appearing to slide down the opponent's, then arcing down, which makes your arms cross and gives this punch it's name.. This is an incredibly powerful punch, but if it fails you are left wide open for a fierce retaliation.
The Hook: The hook can be executed with either the front or the rear hand. Strike out in a subtle arc to connect with the side of the head. Rotate the hand so that the thumb is angled slightly downward on the strike. Aim for the side of the head or the neck. With practice, this can be an effective punch. Practice executing a controlled hook; avoid wild "haymaker" swings from the side, which can be easily seen and avoided by a skilled fighter. Hooks to the body can also be devastating, with a good shot to the liver or kidneys able to drop an opponent in a single blow. Body hooks are a good followup after a high jab, as your opponent's guard will be high and cannot protect against the body shot. Remember, every shot landed to the body gives you an advantage, especially against poorly conditioned opponents. Take their lungs away and the fight is yours.
The Uppercut: This punch comes from below and strikes up against the opponent's body. It is generally effective only from very close range. Dip your shoulder and draw your fist upward, using your hip to provide torque. Don't drop your fist before throwing, the whole motion should come from the knees and hips, and the punch should end up at about your eye level. It helps if you throw this off a slipped or ducked punch, as you are already in the correct position at this point. This is a difficult strike to perfect for an inexperienced fighter, and is best learned by watching serious boxers execute it. However, if it can be landed, it is arguably the most powerful punch you can throw.
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