Shadowboxing is best done at the beginning of your workout. Concentrate on keeping perfect form, and staying totally relaxed while doing it. In the ring, or hitting a heavybag, it's hard to remember to remain relaxed, but shadowboxing is a good tool for developing this ability. What seperates a beginning fighter from a pro, is the ability to relax in the ring, and shadowboxing is a good tool for developing that. Your whole body should be loose, but not to the point of being lazy. Work on developing your handspeed, by throwing punches, concentrating on speed, instead of power. Work on developing the advanced combinations, such as hooking of a jab, or doubling or tripling up on hooks, that are difficult to do on a heavybag. Shadowboxing is your time to see what combinations you think might work, and then try to use them later when sparring. Too many fighters shadowbox for one round, and then jump into a heavybag routine, and that's all wrong. Take the time to get loosened up, and work on your form. Imagine an opponent is in front of you...Imagine he or she is throwing a jab, and think of ways to defend it. Imagine your opponent is throwing right hands, and think of ways to defend....etc. Three rounds of shadowboxing in the beginning of a workout, should be sufficient. Alot of fighters do more. It just depends on how long it takes you to feel loosened up, and ready to fight. It's also good, to use one round of light shadowboxing as the last round of your workout, to cool down.
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