Bending Calibration Question

[opnsysme]

At the recent SHGC I bent a 480 pound bar which isn't anything close to what others were bending, in fact it was more like 1/2 . So my question is, if the bar I bent was calibrated at 480 pounds, which means it took 480 pounds to bend in a vise with no wraps etc. What did it take with wraps? Now I know the thickness of wraps plays a huge difference, but I am really curious. I am a horrible bench presser and have average pressing strength in my shoulders, but none of my upper body lifts equals 480. So I am trying to grasp how someone that can't bench say 315 pounds can bend a bar that requires 500lbs or more of force ? I'm assuming the fact that the bars wrapped to 2 plus inches for DO and putting them farther out on the ends drastically reduces the weight required right? Sorry for the ignorance but I am very very new to DO bending and have only mildly worked the DU bending style. And because I suck at DO I lost my 3rd place position in the contest and really need to bring my bending up to current levels. Also along those lines, what muscle groups directly affect the DO bending style?

[cemery]

I think bars are calibrated by holding the bar in place on both ends, then suspending weight in the midle of the bar. . . until it bends to a certain degree ( I think). The actual bend of this calibrated bar is accomplished with less that the calibrated force using the ends of the bar as levers. This is why shorter bars are harder to bend. . . the levers ( bar ends) are shorter. I'm no expert so you can take this with a grain of salt.

[opnsysme]

Sounds solid Casey, but then with that theory the user (bender) would put weight calibrated divided by two on each end of the bar. But I don't think any one can put 300 plus pounds on the bar with each hand/arm etc. So the thickness of the pad must substantially decrease the force especially if you have thick and very tight wraps. Right? It then makes those wraps like breaker bars whereas the fulcrum moves way out and less (possibly exponentially less) weight to move the bar. But I hope others chime in as I'm afraid I am missing something. Also what muscles do you think benefit the DO the most? Subjectively it seemed those that had stronger chests (Aarron, Mike) had substantially stronger bends?

[matthcarl]

I personally think the shoulders are more involved than the chest, as well as the triceps, but I truly think practicing the specific movement and learning how to focus strength is more important. I'd be lucky to bench 200lbs and push-press a similar amount overhead, but I can bend 6" stock that calibrates over 500 lbs. Derek Graybill, weighing in at 60 lbs less than I do, is a more extreme example. I have no answers on the physics, but there's no way you can make the case that a 500 lb. (or 700 lb.) bend corrrelates to a similar bench.

[opnsysme]

Exactly Matt, I totally agree with you. So thats why I posed the question.

[timiacobucci]

I think it is the range of motion. Even the most shoulder/chest intensive part of the bend, which is the crushdown, is not a bench press. I don't even really understand where you guys are seeing a correlation? The movemnts are not the same at all. And as for how your muscles can generate that much force, I would say it is like the difference between a full atg squat and a 1/4 squat, or a deadlift and a rack pull.

If you want to do something accurate to test this idea I thought about one time was seeing if you could use a cable setup and have the 2 handles say 4" apart and see how much weight you can lift by closing them together chest crushing like a DO crushdown.

I know I can mash a 425 lb valve spring from a big block pretty easy. Totally coil bind and I went and did the test on the same spring myself, so I know it is really 425 lbs. The simple answer is there is no trick, the physics are simple. You really are generating this much force to bend that bar.

[makey98]

Couple of things I thought about.

I am not a physics expert, but I find this stuff interesting so I thought I would take a stab.

Leverage:

You are correct in that the wieght it takes to bend the bar is weight hanging from the middle, not pressing the ends. I would think that the force required would be even less than half of the poundage of the bar because of the leverage from holding the ends of the bar.

Momentum:

Also force is mass x acceleration, and if you can use your momentum of your body and channel that through your arms you will be able to generate much more force than a strict bench press which should stop at the chest.

Range of Motion:

Also, the range of motion that a 6 or 7 inch bend requires is several inches, where a bench press is several feet. So theoretically, you might be able to generate enough force to move a 500lb bench if you could use your bodies momentum and only had to move the bar 5 inches....(obviously this would be dangerous. No one try this! )

[timiacobucci]

So theoretically, you might be able to generate enough force to move a 500lb bench if you could use your bodies momentum and only had to move the bar 5 inches....(obviously this would be dangerous. No one try this! )

5" rom bench. That is a lockout. 500 is not that far fetched and lots of people try this all the time.

I don't think momentum really has anything to do with it. Not many max bends start bending immediately, they usually start very slowly.

There is no way the force required is half as much as the calibration, I have no idea how you guys are coming up with this. If anything the calibration has a physical advantage because it can apply the force directly in the center. This would be similar to a braced bend over the thigh or knee. It is much more mechanically efficient. An unbraced bend does not even have that, you must lever each short end to apply force to the center. If anything this will mulitply the amount of force you need to exert on the ends for the initial kink compared to a dead center calibration.

The only tricky part of this is that with lots of padding you can push inwards more than lever. This gets into the whole folding debate. I'm not commenting on that but for the sake of this discussion, the lever force as measured in the calibration setup I think would most accurately reflect a strict reverse bend with the index finger and thumb touching bringing the focal point of the levers closer to the center as in the calibration setup.

I believe max DO and DU bends with a good amount of padding holding towards the ends of the bar do actually greatly reduce your leverage mechanically on the bar, but it puts your body in a much more advantageous position to crush inwards with great force making the amount of actual levering force you need to apply substaintially less.

[opnsysme]

Actually just be sure I was not saying that a bench press is the same but actually using that as an example movement. actually I was kinda being rhetorical, as in how can someone bend 500+ pound bar and not bench 300. I believe what Makey98 was saying has relevance but also the fact that really thick wraps that are very tightly wound change the move to an upper body leverage movement. I also am not trying to belittle or lessen, just understand and qualify the movement. If I can learn the mechanics of the move I can get stronger in it.

[makey98]

So theoretically, you might be able to generate enough force to move a 500lb bench if you could use your bodies momentum and only had to move the bar 5 inches....(obviously this would be dangerous. No one try this! )

5" rom bench. That is a lockout. 500 is not that far fetched and lots of people try this all the time.

I wasn't saying that a 5" lockout bench is dangerous. My point was that using your body for momentum would be dangerous. It was supposed to be tongue-in-cheek.

I don't think momentum really has anything to do with it. Not many max bends start bending immediately, they usually start very slowly.

I do think momentum has something to do with it. To me it is like the difference between putting your fist up against someones arm and pushing, versus punching someone from 12 inches away. You can create more force with the same object because of the acceleration of the hand.

[timiacobucci]

I wasn't saying that a 5" lockout bench is dangerous. My point was that using your body for momentum would be dangerous. It was supposed to be tongue-in-cheek.

I see, sorry I didn't mean to sound snide.

[Bob Lipinski]

Bending has different leverage. I think (not positive) that longer arms help in bending, maybe because of being able to get in better position, maybe some leverage issues.

[Booyah!!!]

Matt, I did notice at the comp that you would greatly benefit from getting more flexible with your arm placement. I know another Very strong guy like yourself that has the same issue. I had that same issue. What I did was every time I go to the Gym and when I am heated up, I stretch my Pecs and shoulders to the max stretching with my hand on the wall and hit them at a few different angles. I also use exercise tubing to warm up my shoulders every time I go to the gym and before I bend. I treat it like a chest expander and hit the delts in every plane and also over the head to behind the back to assist flexibility. DO bending took me a long time to learn. It would be very helpful for you to do some DO bending with someone that already knows how. Watch a lot of videos, there are small differences in the way people do this. If I were you, I would just use IM wraps for simplicity sake, wrapped approx 1.5 on the ends, at least till you get the technique and get through a couple tougher bends and then start tweaking style and your wraps for some ME non painful bends OH, It seems to be helpful to bend some items a bit over 7", like maybe 7.25-7.5 " to assist in increasing flexibility. Aaron showed us what he was saying was one of Gazza's ideas with a round piece of lexan a bit longer than 7" and approx 5/8" and just flex it to help you get used to bar and hand placement. I need to try this also, seems real cool. Hope this helps.

[matthcarl]

I agree on the comments about felexibility and long arms. In DO position, I can easily touch an 8" bar to my adam's apple with my upper arms 90 degrees from my body. I see some guys only come up to chest level, and I don't think you can get full shoulder power that way.

[opnsysme]

That is definitely a true point in my case, I struggle intensely to get a 6 inch anywhere near my throat. I have to move way way out on the ends. Mike I will definitely work on my stretching before my next episode. I need to get this down, as it is so frustrating to me. At DU I was knocking on the RED door, but last night it was all I could do to bend 3 60d DO!!

[Booyah!!!]

I know how you feel about that Matt. I could not get a 60D without first Reverse Bending it I remember some really helpful words about DO from Eric which helped me to stay with it.. He said he had a time with it and kind of Morphed into it. This also happened with me. Nailzilla also helped me with some confidence and technique issues. AND the videos that were available from the GripBoard were very helpful. Thanks Guys

[naturalstrength]

At the recent SHGC I bent a 480 pound bar which isn't anything close to what others were bending, in fact it was more like 1/2 . So my question is, if the bar I bent was calibrated at 480 pounds, which means it took 480 pounds to bend in a vise with no wraps etc. What did it take with wraps? Now I know the thickness of wraps plays a huge difference, but I am really curious. I am a horrible bench presser and have average pressing strength in my shoulders, but none of my upper body lifts equals 480. So I am trying to grasp how someone that can't bench say 315 pounds can bend a bar that requires 500lbs or more of force ? I'm assuming the fact that the bars wrapped to 2 plus inches for DO and putting them farther out on the ends drastically reduces the weight required right? Sorry for the ignorance but I am very very new to DO bending and have only mildly worked the DU bending style. And because I suck at DO I lost my 3rd place position in the contest and really need to bring my bending up to current levels. Also along those lines, what muscle groups directly affect the DO bending style?

My response to the physics of nail bending is quite simple, because I am a simple man. Wrap the nail/bolt with suitable wraps, place one hand on each end, and apply as much force as you can until it bends. If you can't, drop down a level, bend it and rest. Try to increase again. Repeat as necessary until desired goal achieved. Work gradually and avoid injury as best as possible. Let me hear an Amen!

Edited April 24, 2008 by naturalstrength

[makey98]

I wasn't saying that a 5" lockout bench is dangerous. My point was that using your body for momentum would be dangerous. It was supposed to be tongue-in-cheek.

I see, sorry I didn't mean to sound snide.

No problem. I didn't think that you were rude, I just didn't want you to think I was an idiot. I meant to add a smiley face on the end of the tongue-in-cheek comment, but I forgot. Sometimes the internet is hard to really express tone. Have a good one!

[opnsysme]

At the recent SHGC I bent a 480 pound bar which isn't anything close to what others were bending, in fact it was more like 1/2 . So my question is, if the bar I bent was calibrated at 480 pounds, which means it took 480 pounds to bend in a vise with no wraps etc. What did it take with wraps? Now I know the thickness of wraps plays a huge difference, but I am really curious. I am a horrible bench presser and have average pressing strength in my shoulders, but none of my upper body lifts equals 480. So I am trying to grasp how someone that can't bench say 315 pounds can bend a bar that requires 500lbs or more of force ? I'm assuming the fact that the bars wrapped to 2 plus inches for DO and putting them farther out on the ends drastically reduces the weight required right? Sorry for the ignorance but I am very very new to DO bending and have only mildly worked the DU bending style. And because I suck at DO I lost my 3rd place position in the contest and really need to bring my bending up to current levels. Also along those lines, what muscle groups directly affect the DO bending style?

My response to the physics of nail bending is quite simple, because I am a simple man. Wrap the nail/bolt with suitable wraps, place one hand on each end, and apply as much force as you can until it bends. If you can't, drop down a level, bend it and rest. Try to increase again. Repeat as necessary until desired goal achieved. Work gradually and avoid injury as best as possible. Let me hear an Amen!

Excellent advice Sounds like the KISS principle