All I know is I always keep my first two knuckles in the straight line with my wrist and never, never, never hit anything with the last three. A lot of martial arts guys I knew had a kind of vertical punching style that employed the lower three knuckles but I thought it was weak and had little leverage or even INTENTION behind it (not in karate - those guys always hit with the first two knuckles in a straight punch that twists at the end.) I would imagine you would have to have the bottom line of your wrist aligned instead of the top part in a straight line for more stability if you wanted to use the three lower knuckles for impact, but I don't think its as strong as having the line run straight through the top to the first two knuckles. If you have your wrist loose and hit something hard with the bottom three knuckles you are asking to break your wrist.
I throw a horizontal fist with the thumb pointing slightly downwards. It is easy and natural to land with the first 2 knuckles.
Do you remember the difference it made to Lennox Lewis when Emmanuel Stewart taught him to turn his right hand over to the shape of the opponents jaw? It is not possible to land with two knuckles punching that way.
Couple things: In karate, they're taught to land on the first two knuckles (the two biggest ones). An instructor asked me if I knew why, I said no, and he said 'Because they're the two biggest knuckles!' Karate strikes are bare-fisted and supposed to be extremely precise. You don't aim for the head, you aim for the temple, philtrum, bridge of the nose or something. Those knuckles are generally inflexible and they also concentrate your power on a smaller point, causing more damage. In boxing this is different. You have gloves and handwraps. You throw many more punches, and you aren't going for precise targets. Also, if you make a fist and hold out your arm, the place most in line with your arm bones is right between your middle and ring knuckles. In addition, trying to land on the first two knuckles can cause injuries to the thumb joint--the gloves make it hard to land cleanly without hurting your thumb. So I say forget the first two knuckles. But it isn't really an issue. In boxing, you just want to land leather. You often land on your finger knuckles, and it doesn't really matter. The glove spreads out the impact. Just hit the guy whatever way you can hit him.
I practice karate and we are taught to use the first two knuckles (the knuckles of the pointing finger and the middle finger). These two knuckles are bigger and are less likely to break then the other two. They are generally sharper than the other two also. By that I mean they have a smaller surface area so the power is concentrated to a smaller area. Some martial artists increase the density of their third knuckle so it grows as big as the second. So when they punch, they are hitting with the three biggest knuckles. Wing chun is a martial art which uses the last 3 knuckles. They also punch with a vertical fist rather than a horizantal fist. You should find someone who practices wing chun for an explanation why. I think its something to do with the shoulders. Put your arms out with your palms facing downwards. Then put your arms out so your palms are facing each other as if you're about to clap. You'll find your shoulders are in a more relaxed position when your palms are facing each other. I don't think it matters too much. Like everything, there are different ways of doing things. People have a different philosophy on punching. Its like making a cup of tea, do you put the milk in first or the water? There isn't really a wrong or right answer. This guy explains some ways of punching: [ame]http://www.youtube.com/watch?v=3C8Nkxf6C2E&feature=related[/ame] I don't think it matters too much in boxing because of the gloves.
if your a boxer wearing boxing gloves hit with the bottom 3 and remember what dempsey says go up to a wall and support your weight with the bottom 3 knuckles, at eye lvl they support your weight better vertical and at body lv they support your weight better horizontal so you should be using a vertical fist for eye lvl shots and a horizontal fist for anything below. in a street fight always hit with the first 2 knuckles. you never know how your going to land and you have no glove to protect you its just your best bet to let the two strongest knuckles take the hit.
dempsey's advice works fine for me and seemed to work fine for him thanks for sharing your opinion though. i dont always throw head shots vertical ill throw overhand rights similar to you. more so the advice was ment to point out that dempsey only recommends the vertical fist for head shots and not every punch thrown.
Dempsey fought in a time where boxers weren't as skillful, and the sport was still in its infancy. He would get murdered if he were fighting in the present day. The power from a horizontal fist straight punch is massive in comparison to a vertical fist.
in your opinon....im not going to go about arguing with your if all you have is opinion. while any one reading this can go up to a wall put their bottom 3 knuckles at eye lvl against it and see if a horizontal fist or a vertical fist gives more support and then do the same thing at body lvl and see if a horizontal or vertical fist gives more support.
more support for what though? supporting you leaning against a wall? you know people (the things you're hitting) aren't flat like walls right? Normally boxers keep their chin down so their face is actually at an angle. Now the horizontal fist offers the same support and more power, as well as protection from the raised shoulder. Also, if you aim for an outstretched chin, the surface area is so small no support is needed for your wrist, but hitting with the smaller knuckles makes you metacarpals more likely to break.
Its so sad when people say stupid things like this. Dempsey was a boxer, anything he says about training and human physiology should be taken with a grain of salt. It's like these idiot celebrities that train in the gym for a movie role, after 6 months they give tips and think know everything about fitness when in reality it's just what they've been told by some PT. Don't bother with the "But he was a really good boxer, he could punch hard" blah blah blah, it's a pointless argument.