How to determine if YOU have a leg length difference? (for stronger cycling)

Over the past 12-18 months we have had many requests to discuss leg length discrepancy for cyclists. Notably, how can you determine if YOU have a leg length difference from the comfort of your own home. Length length discrepancy is a very common cause of right or left sided hip and knee pain, and can be a ticket (once resolved) to more power on the bike .

#bike #fitting #tips

[ravnstl]

Every time i watch one of these videos it makes me wish i lived in Australia to have a fit with Neil.

[sharakorr]

This is a great series. Neil giving his insights is always super valuable

[stevestewart-sturges]

Cardboard insole.... genius, that idea alone is amazing... Cheers, Neil!

[cb]

I could listen to this guy all day on bike fit!

[patrickparisienne]

Absolutely fantastic content guys! Neill is doing himself out of a dollar!
Seriously this is great to empower cyclists to fix problems for a better experience, and eventually, a bike fit. Keep it up guys!

[bradleyandrews]

This is the content I’ve been waiting for! Fellow phisio with a discrepancy here and a relatively new cyclist. I’ve been lazy and figured I’d get around to trying a wedge inside my shoe at some point but this sounds much more comfortable and biomechanically correct. Thanks.

[thedownunderverse]

I think on-bike leg discrepancy indicators are as important as off-bike testing. Personally, my saddle height has always been a compromise - if I set saddle height to compliment my right leg stroke, my left leg has to “reach” and toe down. If I set saddle height to compliment left leg, my right leg doesn’t extend enough (and heel can drop). Solution: shim(s) under left leg!

[grantparks]

Another approach is to measure the individual’s height standing on one leg, then on the other leg, or directly measure the femurs, etc. Large differences may require cranks of different lengths, such as my 25 mm difference. I use 172.5 on the right, and 165 on the left. 10:45

[lancescarborough]

You said you would and you did!!!
Thank you!!!

[evrimkaya]

Thank you so much for this. You already solved my issue of having too much weight on my hands by listening your advice of (counter-intuitively) lowering my handle bars.

Thanks to this video my partner was able to confirm that my left leg is 4 mm shorter. (I didn’t tell her which one i was suspecting of being shorter)

I just installed a 2 mm shim. Let’s see what happens. Hopefully it will solve my right side saddle sore.

[maxshen]

Great fitting seris, really helped me a lot of self improvement and solve issues when cycling, thanks!

[ocphil]

Great videos! Thank you!!! I've tried this shim thing with my attested 10mm shorter left leg. Until now there are 2mm under the cleat... Problem especially on my saddle are not gone. Now I'll just try to make it 5mm or 6mm again and give it a run! If Australia wouldn't be the other end of the world...I would make an appointment!

[koDiacc]

I also have a functional leg length discrepancy which is caused by a twisted pelvis. I improved it a lot by off-the-bike work and I feel this should be the approach. using a shim should only be used when having a real leg length discrepancy. whenever its just muscular we should aim to fix the issue, not the symptom. (for everyone: hip flexors, core and glute medius for leveling up your pelvis)

[game-day]

Thanks for this. Neil mentioned using a shim on your other channel and I have discovered I had a lower leg discrepancy from that video. I added a shim around that time which has springboard my training and my performance drastically.

[alterntive]

Having had right leg issues for a while when I heard the cardboard suggestion just to check I felt so dumb not to have thought of that myself 🤦‍♂️😄 Thanks Cam and Neill

[edsassler]

In day to day life, as soon as your foot leaves the ground it can take any path - it’s called freedom of movement, which is why a leg length difference isn’t such a big problem. Clip into a set of pedals and that freedom goes away... I started to study the effects of leg length discrepancies when I started coaching. There’s both an X and Y component here, the shim is the Y offset, the relative cleat fore/aft position is the X offset. I can take measurements, but I’m more interested in the differences in forces generated, which I can’t see. I’m using vector force information while the client is pedaling to see the differences between the two sides. I can even subtract one side from the other, which makes the difference pretty clear. As a general rule, the femur is a horizontal member while the tibia is a vertical connecting rod (which is why you find tibia differences to require larger shims). Very often a client will come in with a pain over the iliac ridge on the longer side. The force analysis shows that they are pushing forward on that side (keeping those muscles from coming out of tension). My answer there is a small change in fore/aft position on the cleats. There isn’t much room there before other problems start popping up...

This series is wonderful, it’s forced me to rethink my fitting process in so many ways. I’m learning a lot, but I still have a New Jersey accent...

[joelsoto]

Thanks Neil! Thanks Cam! Had been reaching out about this specific topic. Thrilled to see it finally up.

[geoff]

I have a 3.5cm discrepancy. My left tibia is much shorter after dodgy 'corrective' surgery. Cycling is much more challenging than it used to be.

[geothunder]

I started with a 3mm shim on my left leg, rode with it for a couple of rides but it didn't feel right. I bought a pack of 1mm shims and started at 1mm and ended up needing another settling on 2mm shim height. It's a world of difference!

[danielfenner]

Thanks again for another great video and love the channel. I like many others have thought I need a good fit but through these videos have tweeked a few things and even had to add a shim on my left leg and after every adjustment have felt better and seem to be riding a bit faster and more consistent.