Common Causes And Solutions To Cycling-related Knee Pain
By Jesse Jarjour
Common Causes And Solutions To Cycling-related Knee Pain
Cycling is a great form of low impact exercise which is usually easy on the joints. Knee injuries however, can be common in cycling and is more so among those who are clipped in. While being clipped in isn’t necessarily a reason in itself for knee pain, it does increase the chances of poor biomechanical alignment.
It is important to immediately assess any knee pain you experience while riding as what starts as a small niggle can quickly grow into something more serious that keeps you off your bike for an extended period of time.
In this post we’ll look at some of the most common causes of knee pain. Because there are many components of the knee and many causes of potential pain in each area this post will be longer than others in our common causes series. We will break this post down to the area of the knee where pain is being experienced and then review the causes and solutions for each region.
Most knee pain causes are driven by either the seat position and/or the cleat position so we’ll predominantly focus on those two areas. There can also be a strength and mobility component to knee pain which we will briefly cover.
Common Causes of Knee Pain from Cycling
As we mentioned above, most of the causes of knee pain from cycling can be associated with either the seat position or the cleat position. Why is this? The knee’s movement is dependent on what happens above and below it in the pedaling chain. Any changes to the seat or cleat position directly affect the biomechanics of the knee, and while they may also change the dynamics of the joint above or below the knee (hip and ankle) those changes are far less likely to cause pain (and damage) to those joints.
Before we dive in too deep, let’s have a quick primer on the anatomy of the knee. Where you are experiencing knee pain can be a significant clue to what the cause of the pain is so it is important that we are all on the same page regarding terminology. Whenever possible we will avoid medical terms and use layman terms for simplicity.
This post will be divided into areas of the knee and we’ll break down the typical causes and solutions for each area.
This post will focus on identifying the primary causes of pain in each reason and give some possible solutions for each cause.
Front/Centerline of Knee:
Pain in the center of the front of the knee generally has one of two causes:
Inadequate knee extension
Improper fore/aft position (hip to foot horizontal offset)
Cause: Inadequate knee extension
This refers to the seat not being high enough to allow the pedaling forces to occur at the right time in the pedal stroke and excess force being put on the joint of the knee while it is still too bent.
Solution: Ensure proper seat height
Since this type of pain is very frequently caused by the saddle being too low the first step is to ensure that your saddle height is in the correct range. To do this you’ll review your fit and ensure that your knee extension is in range and especially that it isn’t too low (a knee angle of >45°). Front of the knee pain is one of the few times we’ll recommend you err on the side of a higher saddle, and a correspondingly lower knee extension*.
Cause: Improper fore/aft position
This refers to how far forward or rearward you are relative to the pedal during the power phase. There are a number of ways this can be measured and assessed. One of the classic measurements is KOPS (Knee Over Pedal Spindle). We prefer to look at fore/aft more holistically in terms of the angles of each leg segment, the total fore/aft weight distribution of the rider, and the hip, knee and foot fore/aft alignment.
Hip/knee/foot alignment can be modified by moving either the saddle forward or rearward or moving the cleats forward or rearward.
Solution: Check Saddle Fore/Aft and cleat position
Since the cleat position has a direct effect on what the fore aft of the saddle will be, the first step is to ensure your cleats are in the correct position. In terms of your fore/aft cleat placement there are a variety of “correct” placements which will depend on the type of riding you are doing. We recommend you start by setting your cleats by following our guide here.
After ensuring that your cleat position is correct the next step will be to ensure your saddle fore/aft position is correct. To assess your fore/aft position you’ll review the “fore/aft” measurement on your fit report. “Aft” refers to you being further behind the pedal stroke and “fore” refers to you being more in front of it. So having the indicator in the “Aft” position means we need to move the saddle forward and vice versa.
Like cleat fore/aft we believe there isn’t a single correct fore/aft saddle position for each rider, instead the optimal fore aft saddle position will be one that complements their chosen cleat position, and saddle height. We recommend you start with your saddle fore/aft in the middle of its adjustable range and make small adjustments from there. If you are experiencing pain in this region of your knee and both your saddle height and cleat position are correct then we’d typically recommend moving your saddle rearward if the pain is in the bottom of your knee and forward if the pain is at the top of your knee.
Inside or Outside Knee Pain:
We’ve grouped inside and outside knee pain together as often they have similar causes but the specific case dictates where the pain occurs. For instance cleats turned too far heel-in can result in outside knee pain, whereas having them turned too far heel-out will likely result in inside knee pain. The most common causes of inside or outside knee pain are:
Cause: Cleat Rotation
Having your cleats set up so they turn your foot too much heel-in or heel-out will often result in inside or outside knee pain. Excessive heel-in will generally lead to pain in the outside of the knee, heel-out will result in pain in the inside of the knee. In both cases the pain will typically be at the bottom part of the knee. It’s far more common for riders to need a slightly heel-in cleat position than any amount of heel-out.
Solution: Ensure Cleat Position is Correct
Use our guide for cleat placement here to ensure your cleats are set up correctly. A tool like the cleat-key can be helpful to gauge cleat angle.
Cause: Seat Height
Seat height can sometimes cause inside or outside knee pain but it is much more common for seat height to cause front or back of the knee pain.
Solution: Ensure Seat Height is In Correct
Unlike front and back of the knee pain there isn’t a great rule of thumb for determining the cause based on where the knee hurts. Because of this the solution is to just ensure you have an appropriate seat height by reviewing your knee extension.
Cause: Inadequate Arch Support
One of the more common causes of inner knee pain is arch collapse. It is very rare for cycling shoes to have the correct amount of arch support in the stock insole. Knee pain related to a lack of arch support is most typically felt in the inside of the knee and is often more pronounced when climbing or doing consistent harder efforts.
Solution: Ensure Adequate Arch Support
Luckily insoles for cycling have come a long way in the past 5-10 years. There is very little need to go with a custom orthotic, but if you wear them for other reasons it might be worth having your podiatrist craft an additional pair. If you don’t wear orthotics then look at an aftermarket pair of insoles from G8 , Specialized , Bontrager , or SuperFeet . Most brands will have a specific method to assess your foot and ensure you select the proper insole.
Cause: Hip/Knee/Foot Lateral Alignment
This refers to how the hip, knee and foot line up on top of each other. If the foot is significantly inside or outside of the width of the knees or the hips this can lead to pain in the inside or outside of the knee. Generally having the foot aligned inside of the hip or knee will result in pain on the outside of the knee whereas having the foot aligned so it is outside of the hip or knee will result in pain on the inside of the knee.
Solution: Ensure Stance Width is Correct
The lateral alignment of these three joints is very difficult to assess at home and it is arguable that perfect alignment is the goal of a fit. Without tools to track the alignment the best approach is to use feel to determine if you need to increase or decrease stance width. Stance width can be adjusted by moving your cleats laterally, or by using longer or shorter axle pedals. Additionally you can purchase pedals axle spacers to add more stance width.
From experience we find that it is rare to need to go narrower than most of the stock setups, but on the other hand it isn’t uncommon for some additional stance width to be beneficial, especially in individuals with wider set hips. Since it is difficult to assess the need for increased or decreased stance width at home we suggest starting with a neutral position and making small lateral adjustments based on feel. A stance width that is too narrow will be felt on the outside of the knee whereas a stance width that is too wide will be felt on the inside of the knee.
Cause: Foot Tilt
Foot tilt refers to tilt and angle of the forefoot and is typically referred to as varus (foot tilts away from the centerline of the body) or valgus (foot tilts towards the centerline of the body). The vast majority of people have some amount of forefoot varus – this will usually only cause pain if there is an excessive amount of tilt which is uncommon. Foot tilt, as it relates to knee pain, will usually result in lower outside knee pain but can occasionally also present on the inside of the knee.
Solution: Ensure proper forefoot support
There are a number of brands that make and sell cleat wedges, but we want to be clear that it is a very small segment of the population that needs intervention like this. In our fit studio we spend more time removing wedges than adding them. We recommended you use wedging as a last resort after ensuring all other possible causes have been checked.
Back of Knee Pain:
Unlike the front or sides of the knee which each have quite a few different issues that can lead to aches and pains, back of the knee pain generally has two cycling related causes:
Saddle Height/Excessive Knee Extension
Cause: Excessive Knee Extension
If you are experiencing pain in the back of the knee it is likely that it is caused by the saddle being too high resulting in too much knee extension at the bottom of the pedal stroke. Knee pain caused by excessive saddle height can manifest anywhere on the back of the knee so the first step with any pain in this area is to check your saddle height.
Solution: Ensure Proper Saddle Height
Since this type of pain is very frequently caused by the saddle being too high the first step is to ensure that your saddle height is in the correct range. To do this you’ll review your fit and ensure that your knee extension is in range and especially that it isn’t too high (a knee angle of <30°)*. If you’ve been riding with a saddle that is too high for quite a while (long enough to develop knee pain) it will be likely that the “correct” height will feel too low. We suggest riding for a few weeks at this lower height before you pass judgment as the vast majority of the time riders will adapt to the new lower position.
Cause: Cleats Too Far Forward
Other than having your saddle too high, the next most common cause for pain in the back of the knee is having your cleats too far forward. Back of the knee pain caused by having your cleats too far forward typically manifests in the lower portion of the knee – below the midline of the knee cap.
Solution: Ensure Proper Cleat Position
Use our guide for cleat placement here to ensure your cleats are set up correctly. When in doubt if you are having pain in the back of the knee, err on the side of moving your cleats rearward. Keep in mind though that moving your cleats rearward results in more knee extension – and excessive knee extension is the most frequent cause of back of the knee pain related to cycling so it is important to double check your saddle height and the resulting knee extension after making this adjustment.
Strength and Mobility and its Impacts on Knee Pain While Cycling
Apart from bike setup, inadequate strength and mobility can also be a root cause of knee pain while cycling. In these cases the bike position can be perfect yet the rider can still run into issues due mainly to a lack of stability or excessively tight connective tissue. There are three main areas that we commonly see. They are:
Excessively tight hamstrings
Excessively tight IT band
Weak gluteus medius
You may notice that all of the above causes are also related to excessive sitting. Unfortunately cycling can have a similar shortening effect on the muscles as sitting. Because a large portion of the population has sitting related postural issues and cycling can exaggerate these issues we recommend you add a strength and mobility routine specifically for cyclists to your weekly activities. We have partnered with Dynamic Cyclists to offer 15% off on their plans and we highly recommend you incorporate them. At roughly 15 minutes per session it’s easy to find the time to fit them in.
*MVF measures the complementary knee angle if you are used to seeing supplementary knee angles simply subtract the reported angle from 180.
Jesse's cycling journey was destined to end in bike fitting after first being sold a bike that was two sizes too big. The resulting chronic discomfort and related injuries transformed into a passion for finding the right riding position. The improvement he experienced after his first professional bike fit inspired a career change from economics to bikes, fuelling a quest to help others unlock the joy of cycling.