As a physical therapist for endurance athletes and a bike fitter, a lot of my patients and clients come to see me because of their lower back pain, both on and off the bike.

And while lower back pain is multifactorial, saddle height is one parameter that absolutely must be examined when it comes to lower back pain with my cyclists.

So how do lower back pain and saddle height relate? Let’s talk about it.

First, let’s talk about the guidelines that we take into consideration when choosing an appropriate saddle height

Knee extension

At the bottom of the pedal stroke, your knee should be at about a 145-155 degree angle

Ankling

Your heel angle should be no more than 20 degrees at the bottom of your pedal stroke

Knee angle

At the TOP of the pedal stroke, you shouldn’t have to swing your knees out at all to get over the top of the pedal stroke.

 These are basic parameters and do change with each person and how their body fits on the bike, but they are where I start when looking at someone who is experiencing lower back pain on the bike.

 Now, the sneaky thing about saddle height is anything outside of those parameters, both high OR too low, can cause lower back pain.

 Let’s break it down

How too high of a saddle causes back pain

If you are experiencing lower back pain and the saddle height is too high, this is what happens on the bike that can contribute to your discomfort on the bike:

·      It will cause your hips to rock to reach the bottom of your pedal stroke. This will result in more motion at the pelvis, which requires the low back to work harder to stabilize the pelvis.

·      A saddle that is too high may cause you to have a longer reach down to your bars. This asks the core to work harder to help stabilize you. If the core muscles can’t do that much work, it will result in the lower back having to take over.

·      Lastly, a high saddle will cause the hamstrings to have to work in a more lengthened position. This places more stress on the hamstrings. Because the hamstrings attach to the bottom of the pelvis, AND the pelvis is already rocking more as noted above, the low back is going to tighten up to try to help ease the ask on the hamstrings.

 How too low of a saddle can cause lower back pain

If you are experiencing lower back pain and the saddle height is too low, these are the things that can contribute to your discomfort on the bike:

·      If your saddle is too low, your quads are not at an ideal length to help generate force through the pedal stroke. This results in the low back having to help and cause pain in the lower back

·      A lower saddle will cause your pelvis to tuck under you. This lengthens the muscles of the lower back, often past the point of where they can work effectively.

·      As mentioned above, at the top of your pedal stroke, if your saddle is too high you will have to swing your knees out to get it over the top of the pedal stroke. This results in more stress through the hip joint, also decreasing stability at the hip and causing the low back to have to work harder to drive force.

If you're struggling with lower back pain during cycling, it may be time to consider a bike fit to assess not only saddle height, but all variables and fit points that can contribute to pain on the bike. Saddle height is a critical factor that can impact your lower back and overall comfort on the bike. A saddle that’s too high or too low can put extra strain on your core, hips, and lower back and result in lower back pain on and off the bike. A professional bike fit can help assess and adjust your saddle height and other key parameters to reduce pain and improve your performance.

My next steps for you:

 1. Download my ultimate bike fit checklist below👇 to find out the 5 fit points I start with for all of my bike fits.
2. Sign up for an in-house bike fit - if you’re in the area of Prescott, Arizona, come visit me at my clinic for an in-person bike fit. Learn more here.
3. Read more about how saddle height can affect your bike fit and comfort on the bike by reading my blog, Hamstring Pain with Cycling and Saddle Height.