Some evidence that asymmetry may not increase injury rates

[sciguy]

With the proliferation of power meters that measure or at least estimate right left balance there seems to be a segment of the cycling community that would have us to believe that addressing asymmetry is very important way to help prevent injury.

While the study kinked below was done with novice runners rather than cyclists the results are rather thought provoking. If in a high impact sport like running asymmetry does not lead to increases in injury rates how likely is it to be very important in low impact cycling?

http://www.ncbi.nlm.nih.gov/m/pubmed/23673088/

Obviously a study done with cyclists riding bikes would be more definitive for cycling.

YMMV,

Hugh

 

[FrankDay]

With the proliferation of power meters that measure or at least estimate right left balance there seems to be a segment of the cycling community that would have us to believe that addressing asymmetry is very important way to help prevent injury.

While the study kinked below was done with novice runners rather than cyclists the results are rather thought provoking. If in a high impact sport like running asymmetry does not lead to increases i injury rates how likely is it to be very important in low impact cycling?

http://www.ncbi.nlm.nih.gov/m/pubmed/23673088/

Obviously a study done with cyclists riding bike would be more definitive for cycling.

YMMV,

Hugh

I don't think this has anything to do with anything. First, the study had to do with novice runners. I would expect that novice runners, being relative novices, would have a dominant leg which would lead to substantial asymmetry, just what they found. And, the general medical principal is that it is muscle balance asymmetry that predisposes the trained athlete (one who has enough base to have presumably trained some muscle balance) to injury, something this study did not look at, as near as I can tell.

 

[CoachFergie]

I don't think this has anything to do with anything. First, the study had to do with novice runners. I would expect that novice runners, being relative novices, would have a dominant leg which would lead to substantial asymmetry, just what they found. And, the general medical principal is that it is muscle balance asymmetry that predisposes the trained athlete (one who has enough base to have presumably trained some muscle balance) to injury, something this study did not look at, as near as I can tell.

Could you even type that with a straight face?

Care to present some data that people are born with such a highly dominant leg that it leads to a substantial asymmetry.

"General medical principle", when did you last hold a Medical licence?

Care to present some data showing that people develop injuries from their asymmetries? Most of the data on chronic injuries suggest that cycling related injuries are caused by too high or low a saddle, too high or low a cadence and too rapid a progression in training.

Most people who have a substantial injury that I have seen as a coach and bike fitter have ended up at that point after an acute injury. Alex Simmons (who I don't coach or have set up) would be a prime example of this. And from what he has shared his asymmetry hasn't limited his cycling fitness.

 

[elapid]

In my job, we often do corrective osteotomies (bone correcting surgeries) for orthopedic conditions, especially cranial (anterior) cruciate ligament injuries, in dogs. When we first started doing this technique, we tried to correct all sort of perceived orthopedic conditions such as pronation/supination and varus/valgus deformities. However, what is normal? Same situation exists for running shoes that attempt to correct various perceived conditions such as pronation and supination. I am naturally a pronator, but wearing shoes which correct pronation have always led to injuries such as patellar tendinitis. Like the dogs I treat, there is no normal and what you are born with, whether it be symmetry or asymmetry, supination or pronation, or valgus or varus, is more than likely normal for you and more than likely there is no "normal" which can be applied across a general population, regardless of how well trained you are or not. Based on my experience, I would believe the results of this study.

 

[FrankDay]

Care to present some data that people are born with such a highly dominant leg that it leads to a substantial asymmetry.

Fergie, you are really just too much. Here is where one might go just for starters to understand why such an asymmetry might exist: http://en.wikipedia.org/wiki/Laterality

"General medical principle", when did you last hold a Medical licence?

LOL. What are your medical credentials to contradict my statement? Facts would be more effective to make a point than ad hominem attacks

Care to present some data showing that people develop injuries from their asymmetries? Most of the data on chronic injuries suggest that cycling related injuries are caused by too high or low a saddle, too high or low a cadence and too rapid a progression in training.

http://www.sportsmd.com/SportsMD_Articles/id/361.aspx

Most people who have a substantial injury that I have seen as a coach and bike fitter have ended up at that point after an acute injury. Alex Simmons (who I don't coach or have set up) would be a prime example of this. And from what he has shared his asymmetry hasn't limited his cycling fitness.

Your point? The issue isn't whether people can perform well with asymmetries but whether such asymmetries predispose them to injury. The fact that one person has an asymmetry and has not been injured YET is not particularly good evidence that such a correlation doesn't exist.

 

[FrankDay]

…and more than likely there is no "normal" which can be applied across a general population, regardless of how well trained you are or not. Based on my experience, I would believe the results of this study.

I would believe the results of the study also. I just stated I thought the study to not be relevant to pretty much anything.

The fact that we are all a little different does not mean that there are no general principles that some "differences" make people more prone to injury or that some differences may make people better at doing one thing or another.

 

[sciguy]

http://www.sportsmd.com/SportsMD_Articles/id/361.aspx.

Frank this site isn't data, it's an infomercial for the doctor's practice.

Hugh

 

[FrankDay]

Frank this site isn't data, it's an infomercial for the doctor's practice.

Hugh

It is a doctor, not associated with me, stating his understanding of the literature. But, here you go. As you will see, this is the general consensus of those involved in preventing and treating sports injuries. If this isn't enough let me know and I will find more.

http://www.ncbi.nlm.nih.gov/pubmed/11533574

We conclude that rotator muscle strength imbalance may play an important role in shoulder injuries in high-level volleyball players

http://www.re-gel.com/Athletes_Almanac/2012/06/18/the-five-causes-of-injuries-muscle-structural-imbalances/
http://www.med.nyu.edu/pmr/residency/resources/Clinics_sports%20med/runner%20muscle%20balance%20core_PMR%20clinics.pdf

This article discusses the importance of muscle balance and core stability for injury prevention and for improving a distance runner’s efficiency and performance.

http://books.google.com/books?id=_IuGSCUhWoEC&pg=PA470&lpg=PA470&dq=muscle+imbalance+and+injury+in+athletes&source=bl&ots=37sfg3drqW&sig=6OeqqsnU8yKbrjODl6Vpibzjyfw&hl=en&sa=X&ei=YaGfUYJIyfGKArHZgagL&ved=0CD0Q6AEwAjgK#v=onepage&q=muscle%20imbalance%20and%20injury%20in%20athletes&f=false

http://www.livestrong.com/article/467303-muscular-imbalance-in-football/

Leaving a muscular imbalance untreated increases the likelihood for an injury. For example, fitness expert Mark Verstegen tells the Core Performance website that 65 percent of all injuries --- from sports and day-to-day activities --- are associated with overuse and muscular imbalances.

http://orthoinfo.aaos.org/topic.cfm?topic=a00408

Muscle imbalance. When one muscle group is much stronger than its opposing muscle group, the imbalance can lead to a strain. This frequently happens with the hamstring muscles. The quadriceps muscles at the front of the thigh are usually more powerful. During high-speed activities, the hamstring may become fatigued faster than the quadriceps. This fatigue can lead to a strain.

Poor conditioning. If your muscles are weak, they are less able to cope with the stress of exercise and are more likely to be injured.

Muscle fatigue. Fatigue reduces the energy-absorbing capabilities of muscle, making them more susceptible to injury.

http://books.google.com/books?id=pF5JXuhDFpoC&pg=PA98&lpg=PA98&dq=muscle+imbalance+and+injury+in+athletes&source=bl&ots=kgY7qDXHYA&sig=0MgmyQ1oYT5-xPtZ5Y1MXluFJlY&hl=en&sa=X&ei=7qSfUZCaAaTBigL52YDQDw&ved=0CDsQ6AEwAjge#v=onepage&q=muscle%20imbalance%20and%20injury%20in%20athletes&f=false
http://www.medscape.com/viewarticle/781422

To suggest that a single paper that simply shows that novice runners do tend to be unbalanced is going to undo years and years of research in this area in which serious professionals, after review of the available data, have concluded that muscle imbalance is a significant risk factor to injury seems a bit much to me.

 

[CoachFergie]

Fergie, you are really just too much. Here is where one might go just for starters to understand why such an asymmetry might exist: http://en.wikipedia.org/wiki/LateralityLOL. What are your medical credentials to contradict my statement? Facts would be more effective to make a point than ad hominem attacks
http://www.sportsmd.com/SportsMD_Articles/id/361.aspxYour point? The issue isn't whether people can perform well with asymmetries but whether such asymmetries predispose them to injury. The fact that one person has an asymmetry and has not been injured YET is not particularly good evidence that such a correlation doesn't exist.

I ask for data and you present wikipedia and opinion. Comical.

 

[CoachFergie]

It is a doctor, not associated with me, stating his understanding of the literature. But, here you go. As you will see, this is the general consensus of those involved in preventing and treating sports injuries. If this isn't enough let me know and I will find more.

http://www.ncbi.nlm.nih.gov/pubmed/11533574

http://www.re-gel.com/Athletes_Almanac/2012/06/18/the-five-causes-of-injuries-muscle-structural-imbalances/
http://www.med.nyu.edu/pmr/residency/resources/Clinics_sports%20med/runner%20muscle%20balance%20core_PMR%20clinics.pdf


http://books.google.com/books?id=_IuGSCUhWoEC&pg=PA470&lpg=PA470&dq=muscle+imbalance+and+injury+in+athletes&source=bl&ots=37sfg3drqW&sig=6OeqqsnU8yKbrjODl6Vpibzjyfw&hl=en&sa=X&ei=YaGfUYJIyfGKArHZgagL&ved=0CD0Q6AEwAjgK#v=onepage&q=muscle%20imbalance%20and%20injury%20in%20athletes&f=false

http://www.livestrong.com/article/467303-muscular-imbalance-in-football/



http://orthoinfo.aaos.org/topic.cfm?topic=a00408



http://books.google.com/books?id=pF5JXuhDFpoC&pg=PA98&lpg=PA98&dq=muscle+imbalance+and+injury+in+athletes&source=bl&ots=kgY7qDXHYA&sig=0MgmyQ1oYT5-xPtZ5Y1MXluFJlY&hl=en&sa=X&ei=7qSfUZCaAaTBigL52YDQDw&ved=0CDsQ6AEwAjge#v=onepage&q=muscle%20imbalance%20and%20injury%20in%20athletes&f=false
http://www.medscape.com/viewarticle/781422

To suggest that a single paper that simply shows that novice runners do tend to be unbalanced is going to undo years and years of research in this area in which serious professionals, after review of the available data, have concluded that muscle imbalance is a significant risk factor to injury seems a bit much to me.

Congratulations, you have shown you can type "muscular imbalance" into Google. Comical.

 

[CoachFergie]

Frank this site isn't data, it's an infomercial for the doctor's practice.

Hugh

As always one does not debate Frank, merely prods him to see how much further he will sink.

 

[CoachFergie]

Here ya go Frank, will toss ya a wee bone...

http://georgenassis.blogspot.co.nz/2011/06/do-strength-asymmetries-increase-risk.html