Many people have a slight difference in leg length, most of the time by less than a couple of mm. Many people walk around without too many problems, the problem starts when you jump on to your road bike.
Your legs are one of the most effective levers out there but in order to work together they need to be perfectly synced to one another otherwise you end up with uneven power distribution (i.e. one leg doing all the work and the other leg getting a free ride)
Potential problems resulting from a leg length discrepancy
- Shorter leg stretching to pedal causing saddle to chafe on one side
- Back pain caused by one side of the pelvis tilting more than the other.
- Loss of power and speed caused by uneven pedal stoke.
- Achilles soreness from over stretching of the tendon.
- Knee pain from uneven saddle height.
- Hip misalignment which can lead to an even larger total discrepancy.
- Severe over developing of quad muscle (This is surprisingly common – I recently had a case where my client had been riding with a discrepancy of approx 20mm over the last few years without any correction, over this time he had developed a 7cm size difference between the diameter of each of his quad muscles!)
Diagnosis and treatment
Treatment for this issue is simply spacing of the area between the shoe sole and cleat to make both legs as even as possible, the difficult part is the correct diagnosis as what may seem like a 12mm leg length discrepancy may turn out to be mainly uneven hip alignment which requires a completely different form of treatment in the form of intensive physiotherapy and exercises to try and even out the hips. I use a few different techniques to pinpoint where the problem is so that i can add exactly the correct amount of spacers to greatly maximize your performance (every mm counts)
If you have any question or would like to be checked for this issue please do not hesitate to contact us or book an appointment online.