Saturday, May 9, 2009

Weight Training wrecks shoulders?

This is an interesting looking one.

They compared people that trained with weights with a set of controls who didn't.

  • The weight trainers were less mobile. They had decreased mobility when compared with the control group for all active range of motion measurements except external rotation.
  • The weight trainers had strength imbalances. Presumably there was a lack of balance between the pushing and pulling muscles, reading between the lines - people tend to do lots of pushing and little pulling....which leads to such strength imbalances.
So, weight trainers are
predisposed to strength and mobility imbalances as a result of training. The imbalances identified have been associated with shoulder disorders in the general and athletic population; thus, these imbalances may place RWT participants at risk for injury.

It is true. Even forgetting the weights some people train with hundreds of pushups and no balancing pulling moves. This will lead to problems.

It is ironic that those who are training are those who may end up less mobile and on their way to shoulder injuries due to muscle imbalances.

Shoulder joint and muscle characteristics in the recreational weight training population.

Shoulder disorders attributed to weight training are well documented in the literature; however, a paucity of evidence-based research exists to describe risk factors inherent to participation. Shoulder joint and muscle characteristics in the recreational weight training (RWT) population were investigated to determine specific risk-related adaptations that may occur from participation. Ninety participants, men between the ages of 19 and 47 (mean age 28.9), including 60 individuals who participated in upper-extremity RWT and 30 controls with no record of RWT participation, were recruited. Active range of motion (AROM), posterior shoulder tightness (PST), body weight-adjusted strength values, and agonist/antagonist strength ratios were compared between the RWT participants and the control group. Statistical analysis identified significant differences (p < 0.001) between the groups when analyzing shoulder mobility. The RWT participants had decreased mobility when compared with the control group for all AROM measurements except external rotation, which was greater. Strength ratios were significantly greater in the RWT group when compared with the control group (p < or= 0.001), implying agonist/antagonist muscle imbalances. The findings of this investigation suggest that RWT participants are predisposed to strength and mobility imbalances as a result of training. The imbalances identified have been associated with shoulder disorders in the general and athletic population; thus, these imbalances may place RWT participants at risk for injury. Common training patterns are biased toward large muscle groups such as the pectorals and deltoids but neglect muscles responsible for stabilization such as the external rotators and lower trapezius. Exercise selection that mitigates strength and mobility imbalances may serve to prevent injury in this population. Clinicians and strength and conditioning professionals should consider the biomechanical stresses and adaptations associated with RWT when prescribing upper-extremity exercises

14 comments:

Anonymous said...

Not surprising. I had all sorts of mobility and injury issues with my shoulders (and the rest of my body) the first few years I lifted weights. Over time I learned about imbalances and how to correct them and the importance of prehab/rehab etc. and now I am more mobile and less injury prone than I have ever been. But it comes at a price in time and effort as I definitely spend more time on prehab/rehab and recuperative work each week than I do lifting weights. Figure 3-4 hours in the gym with the weights, 5-6 doing the other stuff. But it keeps me in the game and feeling great so I have no complaints.

Asclepius said...

Back bridges are excellent for working shoulder flexibility.

Mechanically, I do wonder if they may cause damage - but having done them for several years there are certainly no signs of injury yet.

I have great faith in our ability to tolerate and adapt to body weight exercises that do not require any equipment.

Dan Hubbard, M.Ed. said...

Comes down to bad programming, technique, and lack of understanding shoulder biomechanics by trainee (or trainer). Watch your average exerciser perform the bench press or a push-up and you will not be surprised at all by the results of this study.

Anonymous said...

So... pull more, push less=more deadlifts and pullups, fewer bench and overhead. The study forgot to mention one thing... weight lifters are STRONGER than non-weight lifters.

Chris said...

Anon

I know they are stronger, but what is the point being stronger if you are injured. You might end up with less function that your weaker friend.

What if you can bench 450lb but can't comb your own hair?

Anonymous said...

I guess what this study shows more than anything else is that most trainees are idiots who haven't done the slightest damn bit of research to find out whether what they're doing is actually healthy for them or not. My guess is that most people who read this blog do not fall into that category.

Anonymous said...

"What if you can bench 450lb but can't comb your own hair?"

Which is exactly the position Dave Tate got into when he got together with Alwyn Cosgrove and worked on his mobility. T-mag had a well-read article on it a couple of years ago.
Surely there has to be a balance between remaining injury-free and gaining more strength than the average non-lifter.

eshlow said...

Horizontal pulling is the thing most lacking in most people's programs. That and external rotation work.

Not surprising data to say the least unfortunately.

Anonymous said...

I think the anon comment that most trainees are idiots is harsh and wrong. Most people, I'm including all of us in this generalization, at least at one time follow prevailing wisdom on these things. It doesn't seem like rocket science and if it is that complicated we are probably doing something wrong. Maybe we really aren't meant to do chronic pushing.

-xtremum

Mister Suss said...

@ xtremum:

I was exaggerating a little bit. But I don't agree that most of us follow the prevailing wisdom, which comes to us from Muscle & Fitness and any personal trainer Oprah or (shudder) Madonna uses (I'm looking at you, Tracy Anderson).

That's not to say the people we follow are always right or that their wisdom is somehow immutable. But FWIW (not a whole lot in the grand scheme of things) I think the people who are dorky enough to read and comment on this blog can probably say with some assurance that they're going about their training with more forethought than the average bench-happy gym rat.

Working out is not rocket science, but it's harder than combing your hair and the problem I've seen most often in gyms everywhere is that most people put about as much thought into working out as they do into...combing their hair. And yes, I've been there, but so what? I was an idiot then, too.

-luke (anonymous comments are lame, my bad)

Doug McGuff, MD said...

Chris,

The shoulder has a very small articular socket (the glenoid fossa) and a large articular surface (the humeral head)...sort of like holding a basketball on a teaspoon. This creates a joint with a very large ROM and a lot of laxity. The shoulder is vulnerable to injury because of this mobility and laxity. Enhanced function of the shoulder joint IMO is actually enhanced by a decrease in laxity and mobility.

Many of the injuries that occur with weight training occur because the subject is using an exaggerated ROM under load in an attempt to increase his strong ROM. Also many movements (such as the traditional bench press) load the shoulder with the humerus abducted and externally rotated which closes up the space that the rotator cuff tendons have to move in. Further, when using too much ROM the load can tranfer suddenly from a large muscle (like the pectoralis or latissimus) onto smaller structures like the rotator cuff with the result being injury.

The hip joint is just the opposite. It has a large articular socket (the acetabulum) and a smaller articular surface (the femoral head). This is more like a tennis ball sitting in an ice cream cup. Despite all the heavy squats and leg presses (and the much larger "imbalance" between the anterior and posterior structures) we don't see many hip problems.

In short, strength training SHOULD decrease shoulder ROM as a means of injury protection. The problem is the form and technique that most people use. Trying to blame "imabalance" belies underlying premises in this study which make its conclusions inaccurate IMO.

My shoulders have never given me any trouble. I have done NO "prehab" for them, and cannot fathom the necessity of spending six hours per week on this.

Doug McGuff

Chris said...

Doug - thanks for a really helpful insight

Chris

Anonymous said...

Wow Doug, few people know what you know! I'm a trainer who specifically requires clients to avoid any extreme endpoints in the range of motion in shoulder movements. I also advise clients that stretching has a fad status without scientific backing. Muscles are weak at their fully extended position which increases risk of injury in hypermobile individuals.

helium said...

> "It doesn't seem like rocket science and if it is that complicated we are probably doing something wrong. Maybe we really aren't meant to do chronic pushing."

Is picking something up rocket science? Absolutely not. But most people have forgotten how to move correctly. Look a 2-3 year old how he/she lifts an object. You'll see a nearly perfect deadlift technique. Now watch an average 20 years old guy/girl lifting anything remotely heavy and you'll see an awful technique.


@Doug McGuff: About what strength levels are we talking here. There are people that can't even deadlift twice their bodyweight yet claim that strength training had never caused any problems. How could it if you've never used any heavy weights in the first place.

About the hip vs. shoulder injury rate: How many people train their shoulders and how many train their legs/hips? If you have a lot more people that train their shoulder than their legs it's obious that the injury rate in the shoulder is higher. How many people that train their legs have strength imbalances in their hips and thus femoral anterior glide syndrome or any other kind of problems? Is there any reliable data source?