Cycling is a low-impact sport and often recommended as a way to recover from injury or surgery so why is it that besides lower back pain, the next most common complaint I hear from riders coming into my studio is knee pain?
While many cyclists experience knee pain, in most cases the cause it isn’t actually their knee. Instead it is due to the other members of the kinetic chain and how they interact with the knee, that’s why I call the knee THE SILENT VICTIM. The knee not the source of the problem but the unsuspecting victim of another body part, most likely the foot/ankle or hip/lower back interface. The knee minds its own business, quietly suffering and only speaking up when the pain is too much to tolerate.
The knee is not the source of the problem but the unsuspecting victim of another body part, most likely the foot/ankle or hip/lower back interface.
Biomechanically speaking, your knee is a simple hinge and only really designed to open and close in one direction and not move laterally from side to side. It is capable of some minor lateral movement but a typical cyclist who rides at a cadence of about 80-90 will spin out about 5000+ pedal strokes an hour so the slightest knee tracking can result in an overuse injury.
Let’s recap the common knee complaints in the knee:
- Anterior knee pain - Pain at the front of the knee is the most common knee related overuse injury;
- Posterior knee pain - Pain behind the knee is far less common. If its fit related it is almost always due to over-extending the knee;
- Medial and lateral knee pain - Pain at the sides of the knees is fairly common are almost always foot/cleat/shoe related.
There are two main problems that cause knee pain in cycling, those that are:
- Body/Biomechanics related
- Bike related
Hip / Lower Back:
Power comes from the core but pedaling starts at the hips
With a strong core, the entire pedaling kinetic chain has a stable base to push against, but if your core is not strong and your are hips are driving your pedal stroke you will experience knee pain at some stage. The knee is THE SILENT VICTIM of the hip as it is forced to do what the hip wants and in most cases knee pain will appear before hip pain.
Foot / Ankle:
The foot is the point where you transfer your power to the bike
The foot/pedal interface is arguably the most important and is often a neglected aspect in bike fitting. It is the point through which your body’s power is transferred to the bicycle. Many cyclist’s knee pain while cycling is in reality a foot or ankle issue. If you have pronation in your foot through your pedal stroke then the knee will follow the ankle and move laterally and over time will suffer.
Differences in Leg Length:
When one leg is longer than the other
Cyclists with an undiagnosed or uncompensated for Leg Length Discrepancy (LLD) can experience knee pain on the either the shorter leg or the longer leg depending on how the body tries to compensate for the difference.
The return of the weekend warrior
What is often the case when you come back to riding after a break too hard or too soon without proper rest, then your knee may suffer as a result.
Pre Existing Knee Problems
Some things are best referred to a medical professional
There are always those who have pre-existing knee conditions that the rider may not be aware of that may only manifested themselves while out cycling.
Cleat Position fore and aft:
A great majority of cyclists I see in my studio have their cleats set too far forward. Why? Well not knowing any better, when you set up their own cleats for the first time, you tend to set them to the middle of the range provided by the shoe manufacturer which for most is too far forward. Then from shoe to shoe the same position is repeated and the cycle continues. A cleat that is positioned is too far forward may load the knee unnecessarily.
Many riders understand that your knees need to track straight so as a result they set their cleats straight accordingly, makes sense right? Well it doesn’t really work that way. If your cleat is set such that they prevent the foot from staying in it’s natural position then the knee won’t track straight and pain may be the result. Luckily most cleats have some float in them that allows some rotation but some do not. If your foot is forced into an unnatural position it will subsequently twist the knee over and over for your 5000+ pedal strokes an hour… you get the point.
If the feet are closer together than the knees while cycling then you’ll see that telltale V shape from the back. The misalignment of the hip/knee/foot plane causes excessive knee tracking and may result in knee pain.
The solution is to move the feet further apart by adjusting the cleat position, with longer pedal axles or using pedal spacers.
If a rider has their seat too high they will compensate for this by rocking to one side during the power phase of the pedal stroke. The body has to choose one side to protect so it usually chooses your dominate side (in most people it is your right). Protecting that side results overextending the other leg, it’s IT band and knee.
Saddle setback and saddle height are interrelated in such a way that rear setback equates to raising the saddle and pushing it forward equates to lowering it. All things being equal, the further the saddle moves back, the more glutes and hamstrings are used. Conversely, being further forward activates more of the quad muscles. If is an imbalance of the glute/hamstring/quad activation there will be stress put on the knee and an overloading of the front or back of the knee be the can result.
If the reach on your handlebars are too long or low and your core is not strong enough to hold you in that position then you may experience knee pain in one of both of your knees as your body compensates as it attempts to maintain stability in long/low position.
Remember your knee is a simple hinge that just want to open and close in one direction without being overloaded. Pain occurs in the knee from cycling is usually from cleat position, foot support, a hip/lower back problem or a foot/ankle problem or any combination of the these.
Be informed and stay safe on the road.
MARTIN CHOO MSC, B.ENG