So it is my understanding that all else being equal, a bigger guy will punch harder than a smaller guy due to weight transfer and/or some body mechanics that I don’t really have any clue about. But what if the bigger guy is just pure fat?
Let’s say there’s Guy A and Guy B.
Guy A: 160lbs, pure muscle, zero fat.
Guy B: 190lbs, stripped of all his fat, 140lbs.
They are equal in all other relevant aspects (bone mass, height, reach, skill, etc).
Who would be the harder puncher?
I really really doubt there’s some formula to convert fat weight to muscle weight with respect to punching power.
You really need to justify this statement first.
I don’t box, but I do a boxercise class regularly and hold pads for a variety of people. The prime differentiating factor in punch strength (as measured by my hands) is technique. Weight, height, raw strength have some bearing, but the better the technique, the harder the hit. It is all about timing, muscle recruitment, flexibility and rigidity. So of A or B, the better hitter will win.
Si
Fair enough, but the OP said “They are equal in all other relevant aspects (bone mass, height, reach, skill,” bolding mine. So neither of them has better technique, right? Wouldn’t they be evenly matched in that regard?
There are measurable things you can compare, but you can’t compare skill/technique/biodynamics with any accuracy. You do have a single measure (punching force) that can actually be measured, but is a combination of all these other factors that cannot be easily compared (strength, technique, body dynamics etc). I think the only way the OP could get a meaningful answer is to find someone, measure their punching strength at a low fat percentage, then get them to put on fat but maintain all other training stats (strength, cardio, punching rate) and then remeasure punch strength. Or identical twins, but they would have to perform the same in all measurable quantities.
If that was the case, you are looking at a bit more mass (not much, though, arms don’t contribute much to body weight as a percentage) behind the punch, but at the cost of slower acceleration (due to the additional mass). I don’t think it would actually make a difference.
Si
Powerful punching comes from the stiffness of a punch. Stiffness means reducing the amount of force absorbed by the punchers own body when the punch connects. The punchers weight is a factor in the amount of force and how much will be delivered to the punchee, but the stiffness of the punchers body between the soles of his feet and his fist at the point of impact, along with the accuracy of the punch are big factors also. Given everything else is the same, the puncher who weighs more hits harder. But everything else is unlikely to be the same in reality.
F=mv[sup]2[/sup]
The skill includes how much of the body’s mass gets transfered into the punch and what velocity is at contact.
The same skill level with the same muscle level will have a harder time getting a larger fat mass to the same velocity. Since velocity has an exponential impact on force and mass only a linear one, then excess fat will very likely decrease the power of the punch.
Having thought about it on my way home from work, a simple experiment to try would be to determine punching force (using an electronic punch target), and then repeat with a small wrist weight on the hitting hand. Not perfect, as it won’t capture the nuances of shoulder/torso fat, but it would be a start at determining the effect of nonmuscle mass on punch force and acceleration.
Si
The thing you’re maybe overlooking is that if guy #2 is carrying around an extra 50 pounds, then he’s getting some serious exercise just from that, especially if he’s done enough practicing so that his technique is as good as the smaller guy’s.
Does it help? I dunno. But anecdotally, the guys on the softball team with the biggest bellies could * really * wallop the ball.
Hey if you are going to do it, why not use a weighted vest?
Finagle the hypothetical stated actually less muscle in the heavier guy. To assume the same, as si_blakely does is a stretch already; to assume more goes too far.
The purpose of my experiment was to determine the effect of nonmuscle weight on punch force, with all other variables fixed. I did consider a weight vest, but was unsure about how well it would model weight distribution, as well as being more complex. Once you actually have a valid model, you can apply it to the OPs question, including the specified muscle weight differences.
Si
I have a friend who lost 200 lbs. He is quite literally, half the man he used to be, as he weighs just under 200 now, or at least the last time I chatted with him.
He commented that once he’d lost the weight doors no longer just effortlessly opened for him - I think he said ‘they used to spring open like I was Darth Vader’.
Also, he found out he couldn’t actually swim.
This isn’t going to answer any question, but when I was young I was advised to assess potential opponents by looking at their wrists. A thick wrist meant a harder puncher. After checking out my own (very thin) wrists, I decided to avoid fights whenever possible.
As far as the OP is concerned, I assume that is one of those variables that is equal. My unsubstantiated opinion is that the heavier guy would indeed be the harder puncher.
Provided v = sqrt(a)
Human bodies and mechanics are a damn lot more complicated than simple physics such as F=ma (which is the correct form, BTW, and Energy is 0.5mv^2. This is because the derivative of Energy is mv; recall Calculus 101).
I worked on researching what makes a strong punch with Cecil.
There was a lot of research which did not go into the column, as usual. One paper (Walilko, T.J. et al. “Biomechanics of the head for Olympic boxer punches to the face” British Journal of Sports Medicine 39 (2005): 710-719.) detailed the following:
(emphasis added)
That’s one opinion on the situation, and it’s a decent paper.
However, there are a lot of variables, such as whether you strike with the palm versus the fist, the point of peak acceleration of the arm as it moves, and how you stand and the twisting of the body during the punch, etc. There are several reasons to explain why a heavier person might punch more effectively even with the same net muscle mass. I suggest if you really want the answer, check out the references listed in the Straight Dope column above as a starting point.
just my opinion. there are two ways to deliver a power punch: one is to use a lot of body dynamics to move one’s entire body forward in a lounging movement to maximize momentum in the punch (works best when the opponent is also coming at you so the momentum is doubled.)
the other way also uses a lot of muscle coordination to provide extensional force all throughout one’s body. the two ends to this “extending machine” would be your feet planted firmly in the ground and your punching fist. the best example is a stationary karate forward punch wherein arm, shoulder and hip movements will couse one’s punching hand (the right) to directly oppose your trailing foot (the right foot.) that’s what gives it power.
with both methods, one’s strength AND weight are significant. weight would be put to better use in the second IMO, because one has to be bodily solid and immobile.