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will tire you out and you’ll lose your speed. Next, keep your power at the end of your punches. This means that when your fist strikes the bag your arms are fully extended. By doing this, you have more leverage on your punches and thus more power. Hit the bag with your top knuckles and not your finger knuckles. This will give you a solid punch and reduce chances of injury. A lot of boxers make the mistake of slapping their punches. This means they hit with the knuckles of their fingers.