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Effective punch: muscles or speed?

  1. Apr 17, 2012 #1
    Hello Forum,

    to give a knock out punch, does the arm(fist) need to transfer the largest momentum to the opponent face?

    Does a strong, muscular bicep translate into a faster punch?

    Muscles seem to offer endurance and ability to exert large forces but don't seem to offer much speed...

  2. jcsd
  3. Apr 18, 2012 #2
    I would imagine the triceps (opposite of biceps) is more responsible for a strong punch than a biceps. That said, yeah it's momentum you want. Momentum is a combination of mass and speed, so the faster your arm hits the opponent, the more it hurts. In order to accelerate your arm to this faster speed, you need a force, which your muscle provides. Acceleration is directly proportional to force. So yeah...it ultimately comes down to how strong the muscle is.
  4. Apr 18, 2012 #3
    but bodybuilders, with large muscles, don't certainly move fast.....

  5. Apr 18, 2012 #4
    Yeah well biology complicated the issue a bit. You can have a huge muscle that puts out a lot of force, but can't contract quickly enough to throw a nice punch. This might be good when lifting weights for example, but not when quickness matters. This would be analogous to a fully loaded lorry/ tractor trailer. You can have slightly weaker muscles but they can contract faster, thus realizing their full potential when throwing a punch. This would be a sports bike. You can have much weaker muscles that CAN contract faster, but the very inertia of your arms prevents them from doing so. This would be like a motorcycle trying to push a lorry.

    There are lots of types of physiologies, and depending on how you train you can develop your muscles to do what you want them to. Either way, all else equal, the stronger you are the more you can punch. As you noted, all else isn't always equal though.

    Surely Bruce Lee, in his day, could probably do more damage than Arnold Schwarzenegger. That's not to say Arnold couldn't do much damage.
  6. Apr 19, 2012 #5
    I see your point.

    So, a bodybuilder (large muscles) has a lot of force available but cannot move its arm fast...
    thats sounds counterintuitive, since that large force should make the muscle more very fast (large acceleration)....

    That large force is there, as you say, since they can lift huge weights.

    So, I would say that bodybuilders can develop a large force when moving heavy things slowly, but they cannot generate a large force when throwing a punch (due to physiology).....

  7. Apr 19, 2012 #6
    body builders' power output curve is peaked at low rpm, whereas boxers' is peaked at high rpm,
  8. Apr 28, 2012 #7
    There is also the factor of relaxing the antagonistic muscles. Speed is a function of correct training, not just muscle mass. High reps and high speed with no weight is much better than low reps with high weight or resistance. Big biceps are not what you want.

    Body mechanics is also extremely important. Power and speed come from the rooting in the feet, transferred through the legs, waist, and arms. To punch with power is to use the whole body.

    If you want a fast punch, then you need to throw thousands of punches/day to develop the coordination, relaxation and tension in the right muscles.
  9. May 7, 2012 #8
    Just wanted to throw my 2 cents in.. Bodybuilders train for mass, not for strength or explosivness, although they certianly gain much strength as a result of extensive training. You will find that powerlifters and olympic lifters can lift alot more weight than bodybuilders, and at a much lower bodyweight. Powerlifters and olympic lifters focus on maximum strength and explosiveness. So for increasing punching force I would say train more like they do, get as strong as possible, and as fast as possible.

    Theres alot more to throwing a punch than just bringing up a few muscle groups, the hardest hitters use their whole body to throw a punch, they transfer force from the legs and hips to the upper body.

    Well I really just wanted to clarify that bodybuilders don't train for strength or speed. They traing for aesthetic's, and training like a bodybuilder won't increase punching power.
  10. May 7, 2012 #9
    Who are you mad at?
  11. May 7, 2012 #10
    I'm not so sure about that...
  12. May 7, 2012 #11
    Speed and force are both important, but other things are more importamt if you want a knock out punch.

    You must hit the target at the right place and at the right angle.

    You must follow thru so that you continue to deliver force. Bruce Lee used to say never throw a punch at a man's face. Aim for a point behind his head.

    No punch is greater than its reaction force. So you need to position the rest of your body to provide the best possible reaction force. This was Lee's greatest skill and the reason he could out punch Arnold.
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