How to Identify and Fix Your Strength Imbalances

by | Dec 27, 2018

Runners tend to a have one leg that’s stronger than the other. This asymmetry is typical (and not just in runners), but it can significantly limit your running performance and lead to injury. In this article, I show you how to test your body, find your imbalances and, most importantly, fix them!

Firstly, asymmetries are normal. Humans aren’t built symmetrically and we use the left and right side of our body differently. As we develop and learn to write, throw and kick, we predominantly use one side and gradually develop movement habits that create these asymmetries. Over time the strength differences between the left and right side become subtle and feel completely normal. So, it’s difficult to notice until you do an exercise that requires you to do the same movement on the left and right side.


How Asymmetries Cause Injuries

In day to day life, it doesn’t matter that one glute is slightly stronger than the other. You still walk upright and get from A to B without any issues or pain. You probably never even notice that you have a muscle imbalance. But, when you’re running it’s different! During strenuous exercise, your body is pushed to its limited and small asymmetries are magnified. Muscle weaknesses that were never noticed during walking can now cause big problems while running. That’s because weaker muscles fatigue quicker and force other muscles (muscles that shouldn’t be doing the work) to step-up, take over and overwork. That’s what eventually leads to injuries.

Lots of running injuries are caused by muscle weaknesses like this. In fact, the majority of injuries I see in the clinic are overuse injuries caused by muscle imbalances and asymmetries. Things like muscle aches and strains, tendinopathies and joint injuries could all be prevented with better strength training.


How Asymmetries Limit Your Performance

Let’s take a closer look at one muscle in particular – the glute maximus. This is arguably the most important running muscle. It’s your biggest hip muscle and responsible for much of your speed and power. So, what happens when the glute max is stronger on one side? Even though the weaker side fatigues quicker it doesn’t stop you running. Instead, your body finds other muscles to help out so that you can keep on going. But, these supplementary muscles are simply not as good as the glute max so you’re not going to get the same output. This forces you to slow down, even though your other side has more to give.  So by simply strengthening the weaker side, you’ll develop more endurance, power and speed in your runs.


Find Your Asymmetries

It’s very difficult to feel asymmetries while running. Even trained professionals watching a video analysis often can’t pinpoint exactly which muscles are weak. To find muscle weaknesses, we really need to test each muscle individually and compare the left and right sides. It pretty simple to do and, you can actually do it on your own at home.

Here are the tests you need to do:

#1: Calves
Description: Stand on one leg, holding on to something lightly for balance. Lift your heel up, rising onto your toes then gently lower your foot down. Repeat on the same leg for as many reps as possible. Take note of the reps. Do the same exercise with the other foot and compare the scores. There should be less than 5 reps difference between sides.

#2: Balance
Description: Stand on a small cushion or rolled up yoga mat on one leg. Don’t hold on to anything. Time how long you can maintain your balance. Repeat on the other side and compare the time. There should be less than 5 seconds difference between sides.

#3: Hamstrings and Glutes
Description: Lie on the floor and perform a single leg bridge for as many reps as possible. Repeat on the other side and compare scores. Ensure that your pelvis stays level and the exercise technique is the same on both sides. There should be less than 5 reps difference between sides.

#4: Hip Stabilizers
Description: Lie on your side and slowly move your top leg up and down. Repeat for as many reps as possible moving with a slow, steady pace for each rep. Once you’ve reached fatigue, do the same thing on the other side and compare your score. Ensure that your pelvis stays level and the exercise technique is the same on both sides. There should be less than 5 reps difference between sides.

#5: Obliques
Description: Lie on your side and prob up into a side plank position. Hold this position for as long as possible, taking note of the time. Repeat the same thing on the other side and compare the time. There should be less than 5 seconds difference between sides.

Fix Your Asymmetries

Once you know where your asymmetries are you can start fixing them. It’s easy to do once you have a program in place. After a few months you can do a re-test and see just how much you’ve improved!

Your training goal will be to close the gap as much as possible, not necessarily aim for perfect symmetry. Remember, our bodies aren’t designed to move identical on each side so it’s normal to have small strength differences.

Rule 1: Always start with your weaker side

You’ll find it more natural to start a set of exercises with your stronger side. But be conscious and start with your weaker side. By starting with your weaker side, you’ll have more energy to invest in this side.

Rule 2: Never do more reps on your strong side

Another benefit of starting an exercise with your weaker side is that you will know how many reps you can do. If you’re getting fatigued by 7 reps on your left leg and stop, don’t do any more than 7 reps on your right.

Rule 3: Add a few extra reps at the end

Once you’ve completed all the reps and sets for an exercise, try to add one extra set on your weaker side. Over time, the extra workout will build up your strength on the weaker side.

Rule 4: Focus on form 

It’s easy for weaker muscles to cheat and avoid switching on. You might notice that when you do an exercise with your weak side, your form is harder to maintain or you move faster through an exercise. These are both compensatory techniques that happen as a result of weak muscles. To avoid this, go slower on this side and really focus on how you perform the movement.

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Alina is an Australian Physiotherapist, Strength & Conditioning Specialist and avid runner. She works exclusively with runners in injury rehabilitation, prevention and performance improvement. Learn More Here

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