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Discussion Starter #1
I have seen a couple of post lately about heavy stabilizers and heavy bow will cause injury. The statements were that the bow moves back before it moves forward.

With a high caliber rifle the recoil is less with a heavy rifle. So why would the recoil not be less with a heavy bow?
 

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Well, one person says "this" and another says "that." Bows have recoil, but not like a firearm, so I doubt the same "kick" by a long shot (no pun intended).
Weight can help and too much can hurt. The gentlemen with his daughter noted 3 ounces up front and 8 ounces on the back. If on my bow that proved too much weight. Yep, I thought I wanted over 8 pounds and at first it felt pretty good, but after a time it proved too much. I now have 2 ounces up front and 5 ounces on the back. Total, my bow weighs about 7 1/2 pounds.
 

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Discussion Starter #3
I understand that a bow that weights too much would cause fatigue very quickly. I added too much weight to my bow and I had shoulder pain and sore muscles. I think that this was caused by just holding the weight at shoulder level. I reduced the weight back to 8 lbs and 1 oz and now I don't have any problems. I want to get the bow back up to 9 lbs just to do some more experimenting.

I am a little hesitant to add the weight because I don't want to be injured. This is why I am trying to understand how the extra weight can or will cause injury.

My bow is shooting a 440 grain arrow at 208 fps. I am probably pulling about 45 lbs. So I am not dealing with the recoil of a 70 lb long bow.
 

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You can't really compare shooting a target rifle with shooting a target bow. The rifle is an open system where the shooter is acting primarily as a brace for the rifle's recoil as it is fired at the target. With the bow, the shooting system is closed and the archer is acting as a fulcrum; standing between the oppositional forces being applied during draw and the shot execution, while simultaneously holding the system steady in 3-dimensional space toward the target.

This arrangement makes it paramount to correctly balance the bow's forces acting upon the archer during draw and shot execution with those he/she are holding (draw weight, holding weight, and mass weight) in that 3-dimensional space with proper bone-on-bone form.

When the draw weight, holding weight or mass weight exceeds the optimal levels for the shooter, the mechanical forces applied to the archer during draw and execution become unbalanced, bone-on-bone alignment is lost, and the archer is then placed in a position where he/she can more easily suffer subsequent injury to the supporting structures (shoulders, wrists, and/or elbows) over time.
 

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Discussion Starter #5
I can't argue the statement that a heavy bow can cause injury. I am not able to understand all the dynamic forces and bone on bone alignments.

I went out today and added another pound of weight which brought the total weight up to 9 lbs. Over a period of 4 hours I shot maybe 30 arrows. Now my draw arm tricep feels like it is over stressed. This happened because I started holding harder into the wall trying to keep the front stabilizer up. Maybe a days rest will help with the draw arm.

Extra weight definitely requires more strength to hold.
 

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Discussion Starter #6
I am now trying 17 oz on a 30" stab and 23 oz on a 15" back stab. If I like the stabilizing affect of these stabs and weight, maybe I need to go to longer stabilizers so that I can reduce the weights.

Would longer stabilizers with less weight be safer to shoot?
 

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2 1/2 pounds of weight? 9 pounds? That'd kill me. Perhaps a look at your overall set up is needed, bow, arrows, all?

For years I used a 30" stab with no more than 3 ounces up front and pretty much stayed in the top 3 on the local and state sanctioned circuit, 3D and paper. Right before my accident I was testing a item alternating between two bows every 2 shots. Here are the two bows and the target...perhaps a personal best for me...and not what you call a paper shooter. Same arrows used with both bows, 322 grs counting the 80 gr glue-in point (6.04% FOC). Over 40 shots, but called it 398/400.
MX2, counting quick disconnects; 31" and 2 ounces. Two 13" back bars, 3 ounces on left, 2 ounces on right. Up over 8 pounds at one time, but too heavy.
MarXman; With quick disconnect, 31" with 2 1/2 ounces. Bernie's Mini Silencers fully weighted (I forget the weight, but not much). The MarXman shot as good without anything on the back. This last 3D season it shot every bit as good using one 10" back bar and 6 ounces and my worse finish of 18 or more 3Ds was a 4th at ASA Qualifier.
Both bows, right at 7 1/2 pounds each.
 

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I am now trying 17 oz on a 30" stab and 23 oz on a 15" back stab. If I like the stabilizing affect of these stabs and weight, maybe I need to go to longer stabilizers so that I can reduce the weights.

Would longer stabilizers with less weight be safer to shoot?

Example to keep similar as you have now:

Total Rotational Inertia: (30^2 x 17) + (15^2 x 23) = 20,475
Residual Front to Rear Moment: (30 x 17)=510 and (15 x 23)=345; 510-345=165 residual front moment

Few possible combinations:
33" x 14oz and 15" x 20oz; save 6oz
33" x 14oz and 20" x 15oz; save 11oz
36" x 12oz and 15" x 18oz; save 10oz
36" x 12oz and 20" x 13oz; save 15oz
 

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My theory isn't as scientific and most likely incorrect, but here's the exercise physiology response (you mean my degree may actually be a benefit, I no long feel like an art history major)...

First, the heavier bow would have a higher inertia, and in itself should produce less, or better control, recoil.

That being said, trying to hold up a heavier bow, especially if you are not conditioned to do so, changes the alignment of your bone structures. Try holding out at arm's length say six pounds and fifteen pounds (or a weight that feel significantly "heavy," even too heavy to hold with good form). You might notice that you start to engage not only your deltoids butt also your trapezius muscles... You start to "shrug" to hold the weight up and in control. This changes the bone on bone alignment; plus you mentioned pulling harder into the back wall to control the weight- More stress on the soft tissue around the joints. .

So, my $0.03 (inflation) is that there is probably less recoil from the bow, but it is doing more damage because it's into the soft tissue around the glenohumeral and acromioclavicular joints. You can shoot a .22 or .308 all day long, until you set the butt into your shoulder wrong.
 

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^^ What ShootingBlind said. Rifle/handgun perceived recoil is soaked up by weight. Monster rifle recoil will only give you a scope scar. Holding a bow approximately 30 inches from thr fulcrum (your armpit) is a lot of load on the muscle structure of your arm, back and shoulder. I just did a rough calculation and the 8 pound bow requires 90 lbs to stabilize it in your shoulder muscles. Increase to 9 pounds and it takes 101 pounds of force at the same location. And so on. The injuries are from tearing the muscles in the back and shoulder from repetitive stress, not the recoil of the bow.
 

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Discussion Starter #11
^^ What ShootingBlind said. Rifle/handgun perceived recoil is soaked up by weight. Monster rifle recoil will only give you a scope scar. Holding a bow approximately 30 inches from thr fulcrum (your armpit) is a lot of load on the muscle structure of your arm, back and shoulder. I just did a rough calculation and the 8 pound bow requires 90 lbs to stabilize it in your shoulder muscles. Increase to 9 pounds and it takes 101 pounds of force at the same location. And so on. The injuries are from tearing the muscles in the back and shoulder from repetitive stress, not the recoil of the bow.
I can totally get on board with this analysis.

I am going to go with longer stabilizers and less weight. I want to try 36" stab up front with 12 oz of weight. Later I may change my back stabilizer and weight.
 

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Don't forget to view the entire picture. Increasing stab length will allow you to add less weight to your system; HOWEVER, the inertial forces being applied to your body can still be about the same or more likely even increased. Play cautiously....
 

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The issue isn't "recoil" in my mind, it's the abrupt transition between the bow mass being supported partially by the holding weight to it being supported entirely by the bow arm. The way you have the bow supported during the shot and how that changes during release seems to have a pretty significant effect on should injury.

-Grant
 

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Example to keep similar as you have now:

Total Rotational Inertia: (30^2 x 17) + (15^2 x 23) = 20,475
Residual Front to Rear Moment: (30 x 17)=510 and (15 x 23)=345; 510-345=165 residual front moment

Few possible combinations:
33" x 14oz and 15" x 20oz; save 6oz
33" x 14oz and 20" x 15oz; save 11oz
36" x 12oz and 15" x 18oz; save 10oz
36" x 12oz and 20" x 13oz; save 15oz
You also need to consider the moment created by Holding Weight X Distance from your grip center to the arrow. Sure, the lever arm is short, on the order of 2 1/2 to 3 inches, but the weight acting on it is significant.
This moment works with the back bar or vee bars.
This is all good until the moment of release.
Once the arrow leaves, it's just the bow, gravity, and your shoulder as skeletal alignment is reduced or eliminated during the follow through. Weighting the bars and adjusting holding weight to give a quiet follow through is beneficial to reducing fatigue and strain.
You'll also find that once you create enough inertia to make your dot sit nice it will also hinder restoring the dot to the center once it wanders off. It's all a balance of compromises.
 

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My theory isn't as scientific and most likely incorrect, but here's the exercise physiology response (you mean my degree may actually be a benefit, I no long feel like an art history major)...

First, the heavier bow would have a higher inertia, and in itself should produce less, or better control, recoil.

That being said, trying to hold up a heavier bow, especially if you are not conditioned to do so, changes the alignment of your bone structures. Try holding out at arm's length say six pounds and fifteen pounds (or a weight that feel significantly "heavy," even too heavy to hold with good form). You might notice that you start to engage not only your deltoids butt also your trapezius muscles... You start to "shrug" to hold the weight up and in control. This changes the bone on bone alignment; plus you mentioned pulling harder into the back wall to control the weight- More stress on the soft tissue around the joints. .

So, my $0.03 (inflation) is that there is probably less recoil from the bow, but it is doing more damage because it's into the soft tissue around the glenohumeral and acromioclavicular joints. You can shoot a .22 or .308 all day long, until you set the butt into your shoulder wrong.
This makes more sense to me. I've been shooting 8# plus for years and believe it is the root cause of some shoulder issues I'm having. I also believe this has nothing to do with recoil and everything to do with alignment. You don't want to add weight that impacts good alignment, and you certainly want to increase gradually. The OP jumped from 8# to 9# in one increment... no way that could be productive. You need to find the proper front/back ratio and then build your weight off of that. Also, I'm finding with lighter bars you can get the same effect with less weight.
 

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The issue isn't "recoil" in my mind, it's the abrupt transition between the bow mass being supported partially by the holding weight to it being supported entirely by the bow arm. The way you have the bow supported during the shot and how that changes during release seems to have a pretty significant effect on should injury.

-Grant
Game over. This is exactly it.

given proper form when the shot is executed the physical weight of the bow and attachments is transferred from being mostly supported through 'bone on bone' alignment and hence evenly distributed through your body to a sudden (assuming a correct follow through) load on your Brachialis muscle (the one you use to keep your arm outstretched). As Grant says, it's not the recoil as such as you might experience from a rifle but rather a sudden change in direction of the forces when the shot is executed. It stands to reason that the heavier the bow, the more chance of injury.

Jason
 

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Um, I don't think that you should load up a bow for the first time shooting long stabs with a high amount of weight and you should do it just like any other sport and work your way up by putting in the time shooting and getting into shooter shape. I shoot with a 33 inch and 15 in rear stap and I have 20 ounces out front and 33 ounces in the rear and I can shoot all freaking day long without getting tired.

Not only is shooter shape important but shooting with back tension preload in the wall is also very important. If you have a 14 pound holding weight and you are just sitting in the valley you are forcing the front arm and shoulder to do all the work but if you have your draw length set correctly so that you can add some back tension preload to the wall and shoot inside the wall instead of just standing next to it you will find that your rear arm can help the front arm a bunch.
 

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I have seen a couple of post lately about heavy stabilizers and heavy bow will cause injury. The statements were that the bow moves back before it moves forward.
I suspect whoever made the statement needs to revisit their understanding of physics. the only way the bow can go backwards is if a force is applied to move it, and that can only come from the inertia of the arrow. that's far less than the inertia of the bow itself, and when you combine the force being applied by the archer to the bow (equal to the holding draw weight of the bow) that will result in the overall movement being forwards.

the only way I can think you're going to injure yourself with a high mass weight bow is something like a rotator cuff injury, and we're talking about 5-8lbs here unless you are running Reo-level amounts of stab weight, in which case it's about 10lb max.

you're more likely to hurt yourself with a high draw force (often incorrectly referred to as draw force) when you get into muscle and shoulder injuries.
 

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sometimes reality hurts
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I have seen a couple of post lately about heavy stabilizers and heavy bow will cause injury. The statements were that the bow moves back before it moves forward.
I suspect whoever made the statement needs to revisit their understanding of physics. the only way the bow can go backwards is if a force is applied to move it, and that can only come from the inertia of the arrow. that's far less than the inertia of the bow itself, and when you combine the force being applied by the archer to the bow (equal to the holding draw weight of the bow) that will result in the overall movement being forwards.

the only way I can think you're going to injure yourself with a high mass weight bow is something like a rotator cuff injury, and we're talking about 5-8lbs here unless you are running Reo-level amounts of stab weight, in which case it's about 10lb max.

you're more likely to hurt yourself with a high draw force (often incorrectly referred to as draw force) when you get into muscle and shoulder injuries.
 

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I suspect whoever made the statement needs to revisit their understanding of physics. the only way the bow can go backwards is if a force is applied to move it
You have obviously not watched many slo mo videos of the release or paid close attention to what your bow was doing in your hand..... Here a video that clearly shows how the bow first moves back into the hand before bounding forward: watch from 0:22 mins


The force being applied is the forward movement of the limbs at release--Remember that equal and opposite reaction stuff. This is obviously less evident with parallel limbs that move in more of an up and down manner.
 
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