Strength Imbalance: Training Your Weaker Side

Strength Imbalance: Training Your Weaker Side [Ep40]

How to Fix Strength Imbalance

When performing various exercises, if it feels like there’s a strength imbalance and your right side is stronger, or more stable than the left, this is something you might want to work on…

So this video is actually in response to a question that came up from one of our Bulletproof Runners Programme members.

I’m asked so frequently about how to fix asymmetries in strength, stability and mobility that I wanted to share my approach to working on the weaker side, in the video above!

Do you have a weaker side?

It’s not uncommon for runners to perform exercises such a single leg squat, lunge, side plank or single leg bridge, all of which challenge the body asymmetrically, only to find that performing the exercise on one side feels very different to the other.

One side might feel stronger, one side might fatigue quicker, one side might feel tighter and more restricted, one side might display really poor balance and stability compared to the other.

All of these are slightly different situations, and all are fixable with the right approach.

So, how do we solve a strength imbalance like this?

Well I want to think of two different categories:

  • Strength & Mobility
  • Stability & Postural Control

Let’s start with strength and mobility.

A good context here is to talk about a single leg bridge. In doing this exercise, many runners will feel that one side feels weaker than the other, and fatigues more quickly. You may also feel that one hip feels tighter and more restricted than the other.

Often this kind of strength imbalance comes as a result of injury. Let’s say that our runner doing the single leg bridge is rehabbing a hamstring strain. He may well be weaker on the affected side as a result of the injury, and perhaps a little tight around the same side hip as a result of having to protect the injured leg.

Where we’re building strength on this weaker side, to correct a strength imbalance, I usually get runners in this situation to work to a 2:1 ratio of sets. So for every set of an exercise they do on the strong side, they do two sets on the uninjured side.

The same principle can be applied when it comes to doing mobility and stretching work to address your tighter hamstrings for example.

Now when it comes to stability and postural control, I take a slightly different approach. Rather than getting the runner to double-up on reps on the less stable side, I’d rather focus on reinforcing good patterns – starting from scratch if needs-be.

Let’s take the single leg squat for example. If your programme calls for 3 sets of 15 single leg squats, and you can do so on the right easily, but the left is wobbly and unstable after 5 reps, the last thing I want you to do is plough through the remaining reps regardless.

If right now, 5 reps is your limit, then we turn 3 sets of 15 reps into 9 sets of 5 reps. The same training volume, broken down into chunks of good form.

After a while those 5 good reps in a row will turn into 6, 7, 8 etc until you can do 15 just as well as you can on the other side.

I hope you find the above helpful. If you have any questions, feel free to ask in the comments below.

Last updated on March 7th, 2021.


  1. Thanks for the tips James! I have naturally been stretching my tighter/weaker side more than the uneffected side but I really never tried strengthening it more, hope to put this into practice right away! Nikki

  2. Hi. Ive been struggling for about a year now to get rid of stiff knee due to injury and ITB. Any help would be much appreciated.

  3. So for every set of an exercise they do on the strong side, they do two sets on the uninjured side. Is it correct???? Or two sets on the weaken side?

  4. Hello James, thanks for the tips, Im currently trying to work on my core muscle imbalances as well as hips and legs, I’ve sort of recovered from an ankle injury but I can’t seem to have the muscles on one side of my body do the work, even with unilateral exercises, It still feels like I’m using my strong side for most of the work, what do ? Please help, thank you. Jun