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Heavy bows and injury

5K views 43 replies 18 participants last post by  SonnyThomas 
#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?
 
#2 ·
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.
 
#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.
 
#4 ·
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.
 
#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.
 
#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?
 
#8 ·
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
 
#7 ·
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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#9 ·
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.
 
#15 · (Edited)
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.
 
#10 ·
^^ 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.
 
#12 ·
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....
 
#13 ·
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
 
#16 ·
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
 
#17 ·
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.
 
#18 ·
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.
 
#19 ·
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.
 
#20 ·
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.
 
#21 ·
The limbs/cams (on some bows...more parallel means less forward movement) and the arrow. (Pretty much what Montigre said)
While the arrow IS much lighter than the bow, it also moves a lot more than the bow.
If your holding 30% of the peak weight of the bow at anchor, as you release, the arrow (and the bow...equal opposite as mentioned) now see 100% of the peak weight of the bow.
It WILL move back on the shot.

Here is a bow with parallel limbs (not much movement from that) where you can clearly see the bow move rearward on the shot before moving forward.



On follow through, the shoulder maintains it's level of effort, basically slowing/controlling the speed at which the bow drops.
 
#23 ·
Had a discussion with my Therapist. Holding weight, whether heavy bow or draw weight, isn't the only contributing factor of possible injury. It's turning loose that weight at firing that can hurt. Yep, according to my Therapist there is...a jarring or shock reaction of sorts going from heavy to zero instantly.
 
#25 ·
I'd bet this is more likely the cause as well. Nothing is more harmful than shock loading, so I suppose shock-unloading could be a factor. I would think in this case that a heavier bow would absorb more of the energy and reduce the likelihood of injury. :dontknow:
 
#30 ·
the cams are reeling in the string against the resistance to movement the weight of the strings and the arrow has as it accelerates from a standstill. this is classic, "for every action there is a equal and opposite reaction",....so yes, the cams' reeling in the string against the acceleration of the arrow's weight does indeed force the bow back first and it's recoil is when the mass of the limbs moving forward, come to a stop, that inertia moves the bow towards the target.
the design of parallel limbs is attempt to eliminate as much of this lateral action, reaction and recoil as possible, by diverting a large portion of it into vertical forces which aren't transferred to the shooter's hand because of equal opposing forces in the same plane, witnessed by the lack of forward jump the parallel bows have on the shot.
this has actually made the rearward recoil of reeling in the string and accelerating the arrow's weight more apparent, because the jump forward, as felt in conventional bows has been all but eliminated.
 
#31 ·
Bow as shot (yes I nocked an arrow) a Hefty, massive, shoulder-wrenching, "meine damen und herren how does he do it" 5.8 pounds... Of course my sight weighs over 11 pounds, thank the archery spirits it sits on the ground.
 
#33 ·
Lets look at this action reaction from a different perspective. You are standing 10 feet down range with a shield in your bow hand with the shield supported at arms length. The arrow is going to be shot into the shield.

Now do you want a shield that weighs 1 lb or do you want a shield that weighs 10 lbs. I want the heavier shield because it will absorb the energy and move slower that the lighter shield.

It seems to me that the heavier bow is going to react slower which would be a good thing.
 
#35 ·
It seems to me that the heavier bow is going to react slower which would be a good thing.
Jim, you're right to some extent. The heavier bow will react slower, but you should also remember the second part of the equation, once it is in motion, it is also going to take a greater force to bring it to a stop.

So to use your example, I think I would prefer a shield that weighs around 5 pounds that will allow me to more easily keep it placed over my vital organs without wavering or my arm over tiring, but would also want it to be made of a material that is dense enough to actually stop the projectile. Even the Medieval knights wore a padded cloth/leather (and later chain) coat under their heavy armor to provide added protection against piercing blows the armor did not furnish on its own.

As I have been saying all along, adding weight is not a bad thing--it does provide for a more stable shooting experience. Adding too much weight or adding weight too quickly is where people get themselves into trouble.....
 
#36 ·
I have a very arthritic knuckle between my thumb and hand as a result of shooting a bow with allot of recoil for many years. it is painful enough after several shot to make stop shooting. shock from relaxing the hand to bone-to-bone contact and them violently unloading that contact has slowly aggravated to joint to the point that it gets inflamed ad very sore after only a few shots. repeated actions will cause damage just as easily as heavy loads and impacts, it just takes longer to culminate .
 
#40 ·
A point well taken. People don't realize what muscles or bones are in use drawing/holding a bow until they hurt.
 
#37 ·
Being that the rearward movement is only happening as the arrow is on the string during the shot, the amount of time it is actually moving rearward is very small.
The body absorbs this movement but is not the only force resisting the rearward movement.
Once the arrow leaves the string the momentum of the cams and other parts of the bow now pull the bow forward (provided they had forward movement during the shot. Beyond parallel limb bows will have very little of this).
So while the weight of the bow does increase its rearward momentum, the heavy bow does move back slower. This means it has less travel before all the things that force the bow to change direction do so.
So overall, the heavy bow does transfer less energy to the body due to its slower rate of acceleration x lock time of the bow.
Personally, I believe that this is mainly dealt with by the wrist. The elbow likely takes some, and the shoulder very little.
However, the shoulder still has to deal with a very sudden transfer of weight, and the shock of the bow changing direction back and forth very suddenly.
I think exercises that develop the shoulder muscles in a manner that uses a much larger range of motion.
One of the things that cause carpal tunnel syndrome with people who type is the small range of motion the muscles/ligaments use while typing.
With my shoulder injury, my Physical therapist made sure to use exercises that eventually used the full range of motion.
Long story short. If we would spend the time to properly exercise the shoulder muscles, we could prevent the injuries in the first place, and wouldn't need to worry about the weight of the bow and/or the recoil generated.
 
#38 ·
Mahly, Randy Ulmer once posted of the draw elbow being a "shock absorber."

I've had carpal and cubical tunnel surgery done on my bow arm, both surgeries done at the same time. Even with issues of feeling, dropping things, my shooting never suffered.
 
#39 ·
I'll have to read through all of this later. For whatever reason I've always shot heavy rigs. I've only shot my best scores with very heavy bows. Currently on my PXE40 with Spiral Pros at 59.5lbs I can only seem to aim well and execute what feel like good shots with 40oz on my bars. Shot my best indoor rounds with this rig with 2 15" back bars with a total of 30oz out back and my front 30" rod with 11-12oz of tip weight. Shoot the same bar setup for my best field rounds as well. I'm struggling now though, target face is down for awhile and I'm back to focusing on me. I tried shooting a light bow by light I mean like 8oz out front and 16oz out back on the same rig but a single rear rod, and it seemed to hold terribly for me. As far as injury is concerned I never have had front shoulder pain or issues (yet) I shoot basically 5-6 days a week for well basically 7hrs or so, in 2 years of doing this daily for about that period of time 200ish+ arrows I've missed maybe 3-4 weeks total of shooting one because of a wrist injury from a road bike accident, a week on vacation, then just being sick. Since I'm starting to struggle and not see improvement, I'm going back to ground zero of BB and short range stuff. It kills me because I was shooting the best I've shot and it all collapsed, missed yet another big tourney this weekend because of lack of faith in myself and my shot. I'm not sure how people are injuring the front shoulder because of mass bow weight, I'm sure I'll end up injured on the front half and the back half eventually. I'm just not sure how people can shoot a light bow. I'm to the point if I shoot a light weight bow and I need to move the bow on the target it moves a mile, it all takes time for muscles to learn to control new stab setups etc. Back to ground zero and no target and no competitions for awhile :(
 
#41 ·
I don't think rearward recoil of either the bow or the release hand could possibly cause injury. One the one hand if the rearward force of the bow was causing injury then nobody would be capable of shooting a pistol without injury. In the case of the draw shoulder recurve archers are holding a lot more weight and its not an issue for them.

In my mind the problem remains the transfer of the mass from being supported by holding weight to the bow shoulder. This is why I feel arranging your form to take care of the follow through without needing the conscious act of holding the bow up until the shot is complete is critical.
I'd rather have an aggressive, consistent follow through with the bow shoulder than a passive transfer of weight.

Grant
 
#42 ·
Grant, I think the subject went off track and "muddied up" to start with. "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."

Too heavily a weighted bow can hurt a person, not the recoil or released shock of either a light or heavy bow. Where the hurt comes from is not working up to a weight or having too much weight. The body needs time to adjust and one's body can only take so much.

Heck, if recoil or shock was a issue then some the top Pros should be in rest homes, but they are still kicking butt on the archery ranges....If the recoil/shock thing was real how come there are so many Senior Pros and seniors of all ages still shooting?
I just figured fast/rough, 270,000 shots over the past 15 years and my hands and shoulders are just fine...Well, except the shoulder that got screwed up by hitting a froze down block of ice with my ATV snow blade.
 
#44 ·
I can agree with that...........
 
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