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’ll show you how to test your body, find your imbalances, and most importantly, fix them!
Asymmetries are normal. Humans are built asymmetrically and we use the left and right side of our body differently. As children, we learn to write, throw and kick predominantly with one side of our body. Over time we develop strength differences between our left and right side. It’s subtle and feels completely normal so it’s difficult to notice until you’re asked to do an exercise that requires symmetry.
How Asymmetries Cause Injuries
In day to day life, it doesn’t matter that one leg 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 muscle imbalances. But once you start running, it matters.
During strenuous exercise, your body is pushed to its limits and small asymmetries are suddenly magnified. Muscle weaknesses that were never noticed during walking can now cause big problems.
Weaker muscles fatigue quicker. As soon as a muscle fatigues, it stops working properly. This forces other muscles (muscles that shouldn’t be working) to step-up, take over and do more than they’re supposed to. That’s what eventually leads to injuries.
A lot of running injuries are caused by muscle weaknesses. In fact, the majority of injuries I see in the clinic are overuse injuries caused by muscle imbalances and asymmetries. Muscle aches, 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 gluteus 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 one glute max fatigues quicker during a run?
Well, what doesn’t happen is it doesn’t stop you running. Instead, your body finds other muscles to help out so that you can keep going.
However, the ‘substitute’ muscles are simply not as good as the glute max. You won’t get the same output and you’ll slow down, even though your other side has more to give. So simply strengthening the weaker side, will give you more endurance, power, and speed.
Find Your Asymmetries
It’s difficult to feel or observe asymmetries while running. Even trained professionals watching 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:
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.
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.
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!
The goal will be to close the gap as much as possible, not necessarily to aim for perfect symmetry. Remember, our bodies aren’t designed to move symmetrically so it’s normal to have small strength differences.
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 to start with your weaker side instead. By doing this, you’ll have more energy to invest in this side.
Never do more reps on your strong side
Another benefit of starting an exercise with your weaker side is knowing 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.
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.
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, the form is harder to maintain or you move faster through an exercise. These are compensatory techniques that happen because of muscle weakness. Avoid this by going slower on this side and focusing on perfect form.