I Am Going to England to Even Things Out

Do unilateral (or asymmetrical) movements cause injury?

Contrary to the title, I am not an American seeking revenge for events that occurred during the American Revolution. I am talking about bilateral symmetry. What does that have to do with England? Let me explain.

Human beings are made up of an amazingly complex network of muscle, tendons, bones and nerves that allow us to move. It is thought that we possess bilateral symmetry so that regardless of the need of direction we must flee or start our pursuit, we have the muscles to get us there.

If we favor one movement over another, our bodies are very adept in adjusting. Or at least it seems so. This got me to thinking. How many other movements do we make, not just in running, but also in our daily lives, that are asymmetrical? Brushing your teeth or your hair, eating, waving or anything you do primarily with your dominant hand. When you walk, stepping off with the same foot. When you turn right in your seat to back out of a driveway. These are all things that we have been doing for years and years. If it was so bad to have asymmetrical movement, wouldn’t we have a surplus of meds addressing “brushing elbow,” and “wave hand”? We don’t though. So, does exhaling on the same foot all the time cause injury? What other injuries are out there? Running on a crowned road and leg pain? Hmmm.

The more I think of exhaling on opposite feet to prevent injury (I wrote a blog about it http://gotag.life/2018/07/20/every-breath-you-take/ ), I can say for sure that the concentration involved makes the run go faster. I also think my capacity has improved, but I wonder how much of a real impact it has on relieving stress on my body and preventing injury. I understand that there is a stress, but is it at an adaptable level? I think yes. As for the crowned road, not so sure.

I am particularly interested in this idea because of an injury my husband has (or should I say pain-imposed lifestyle now?). It’s been five years since his leg pain came about. He’s been through the ringer with doctors, procedures, surgeries, shots, PT and pills. He still has the leg pain. Every few months I think if we can just figure out how it started, we can figure out how to end it.

He started ultra running in 2010. Up until I ran my 40 miler this last September, I wondered if that could have been the cause. Running for so long couldn’t be good for your body, right? No, it’s fine. Or at least the distance alone wasn’t the reason. I started thinking about where he was logging his miles. Some trails, but a lot of roads as most of his runs were in the dark. Where we live, there aren’t a lot of paths or sidewalks, but there are a lot of crowned roads. 200 plus miles a month for several months on roads that are slanted in one direction (assuming that you are running safely towards oncoming traffic). That can’t be good. But, maybe it doesn’t matter.

It seems like there must be a line we cross where the strength required for the movement along with the level of repetition causes injury. I couldn’t find a lot of studies on it. It’s not absolutely clear if asymmetric use leads to injury, but seems to (see link below). It is clear that asymmetry caused by one injury leads to another. But what about instances like running form?

Lots of people have been there or have observed the runner with form that makes you want to cringe. You think to yourself that they must be hurting some part of their body, but they are fine. It’s a form that is natural to them. Their body has adapted. Probably because the path to that form was gradual. It’s when they try to change it too fast or too much that they get injured.

I found that if an asymmetry is present in one’s form, it is best to slowly introduce symmetry. In the case of running this can be accomplished by doing drills and striders. The volume of these will have a positive influence on your symmetry without changing too much at once. Plus as you gain speed you will slowly improve your symmetry.

But what if you are forcing your body into (albeit slight) change in running form for a very long time. Does running on a crowned road for miles and miles fall into the same category as carpal tunnel? What are the parameters for restricted repetitive movement? Again, my body seems to have adjusted to using my right hand every day without injury. I turn right to back out of the driveway and step off on my right foot all the time, no injury to show for it- where is the line drawn? Or who knows- maybe it’s the opposite hand’s use that’s the cause for the completely random injury!

What I think we should do is move to England, South Africa, Australia or Japan, you know, just for a little while and run on their crowned roads. Then we’ll know for sure, because either the pain will go away or the other leg will be f’d. At least we would know. In the meantime, I’ll continue to do more investigating. Happy to learn some more on this topic as my “Why Random Injuries Happen” bucket is far from full.

Sites Used for Information:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3438024/

The manoeuvrability hypothesis to explain the maintenance of bilateral symmetry in animal evolution

https://www.ncbi.nlm.nih.gov/pubmed/28514948

Demystification of animal symmetry: symmetry is a response to mechanical forces.

https://www.ncbi.nlm.nih.gov/pubmed/21055708

On the bilateral asymmetry during running and cycling – a review considering leg preference.

https://www.runnersworld.com/health-injuries/a20812228/how-to-prevent-common-running-injuries/

How to Prevent Common Running Injuries