I often come across clients who have one side of their body that is stronger than the other. Why does this happen? Is it simply because we were born to prefer one side over the other? Does it matter?
The fact of the matter is that our bodies are asymmetrical and they were made that way. The liver is on the right, the heart is on the left, etc. The issue isn't that our bodies are asymmetrical, it is if we start to pattern in an asymmetrical way that can lead to injuries.
One way this clearly came across to me was the other day when I was walking my daughter to school. She wanted to use her scooter and as we were going along she tells me that her left leg just doesn't like to go on her scooter. Of course not being able to turn off my PT brain, I asked her to try both. See if you can notice anything about the videos below:
Right Leg on Scooter, Left Leg Propelling:
Left Leg on Scooter, Right Leg Propelling:
Here were my immediate observations:
When she had her right leg on the scooter, my daughter's hips were level, her right lower extremity was in neutral alignment, her overall movement was fluid and she looked strong.
When you compare the 1st video to the 2nd, where my daughter stood on the scooter with her left leg, you can immediately see that her left lower extremity is not as stable. Her left knee goes inward (into knee valgus and femoral adduction and internal rotation). She also has a harder time propelling with her right lower extremity because her left leg does not provide a strong and stable base on the scooter. My daughter immediately tries to switch back to her right leg because she just can't go as fast and doesn't feel comfortable on this side.
These differences can be identified at an early age. My daughter is 4.5 years old and already has a strong preference to her right side. Although many of us may think that is normal, we want to prevent asymmetrical strength/preference differences from becoming a problem in the future. Prevention is key!!
In my daughter's instance, we do little challenges to get her to use her left side more. Each time we get to a street crossing on her scooter she switches to the other side to give each leg an equal opportunity. I give her short cues to try to get her left leg in a more "neutral" position (i.e. "Bring your knee out" or "Straighten your foot" or I show her by just moving her leg into the position I want it to be in). She took to this really well and gets excited to make her left leg stronger.
In the past I have also encouraged my kids to use reciprocal gait up and down the stairs - meaning you alternate each foot with every step going up and down - once they were physically able to. There are definitely ways for you to test your own strength differences by comparing side to side as well. Things like single leg balance time, the amount of weight/reps of an exercise you can perform on one side versus the other, etc.
Ultimately, it is very common to notice differences between your right and left side...and that is ok. What we want to make sure is that we address any weaknesses due to these asymmetries that can cause your body to compensate in a way that can be harmful over time. And of course, the sooner you identify these differences and take the steps to address them, the better!
If you have any questions on this post, please feel free to reach out to me at firstname.lastname@example.org.