Solving Knee Pain on the Bike // Tissues involved // Where is your pain?
https://vimeo.com/259956584/df7f664cb3
Tissue Injury - Location
cycling knee pain
Quad and Patellar tendons
How is it irritated
Generally both these tissues are irritated with excessive knee flexion. Maximum knee flexion occurs at the top of the pedal stroke which is also the time when we begin the loading phase, or our power stroke begins which adds to the stress of these tissues. Knee flexion with force production is a recipe for a tear in a tendon.What fixes can help? Raise saddle, move saddle back, shorten cranks
Mechanics of Injury
The patellar and quadriceps tendons are injured in so similar a way that we can essentially take a look at them together since they share the same cause and mostly the same management.The way these tendons are injured is through a stretch under force. Again, as a quick review, the tendon is in the act of being stretched while it is being loaded when the quadriceps activate to exert force down on the pedals. This happens towards the top of the pedal stroke, when the crank is near “12 o’clock” -- the knee is bent the maximum it is going to be during the pedaling cycle and this is also when the large muscles surrounding the thigh begin to become their most active in pushing on the pedals.The more the knee is bent, and the harder the cyclist is pedaling, the more strain is going to occur at the patellar and quadriceps tendons. Increase in strain leads to more disruption of fibers and more potential for inflammation and pain to spiral out of control and a persistent injury is born.
Sub-patellar tissues are irritated in a different way, however roughly the same set of bike fit issues can bring it about. Sub-patellar cartilage is irritated when it is compressed against the femur. As the knee flexes more the quad and patellar tendons pull on the kneecap from both ends and press it into the femoral groove. Given time and repetition, this can lead to injury.How do we get increased knee flexion at the top of the pedal stroke? The most common way is to have your saddle too low. This is not new or earth-shattering information.
What you’ll see/measure
As you’ll read in the Bike Fit Fixes section, having too low a saddle height is one of the more common causes of patellar and quadricep tendon irritation, but this is one of the most deceptively difficult things to remedy. When the saddle is too low, not only will the knee be bent or flexed at the bottom of the pedal stroke, but more importantly, it will bend more at the top of the pedal stroke. Typically in a bike fit we're looking to have the rider's knee extension angle at the bottom of the pedal stroke between 35 and 45 from full knee extension
Without being able to measure, a rider will only experience the fact that their knees are far from straight at the bottom of the pedal stroke.Just determining what “too low” or “too high” is can be incredibly difficult, since some riders will fall outside the range of what is considered a “normal” saddle height for a person their size. It’s also a very fine line between what is mechanically functional for a rider, and what will cause a problem -- usually as little at 0.75” (or 18 mm) in either direction.
Rider Report | What does it feel like?
Of course, the knee discomfort is usually located on the front, but it’s the nature of the pain that can differ. Quad tendon irritation will reside above the knee cap while patellar tendon lives below. The pain is often, but not always, present to start rides. As the rider becomes more fully warmed up, then it can often lessen or disappear, only to return again at the end of the ride as the rider fatigues.Pain off the bike is possible - especially when going up and down stairs, running or squatting down, but often the pain won’t be present during normal daily tasks.
Let's go over some basic bike fit fixes (but more on this later)
If you believe that, indeed, a low saddle is the cause of your knee pain, the simplest way to start is to raise the saddle in 5 mm increments. This sounds easier than it is because there are a lot of things to keep in mind -- most people fail to heed these which prevents them from fixing the problem:The conventional wisdom is that pain in the front of the knee means your saddle is too low, and in many cases this is true. But while this simple rule is correct often and can solve this problem a lot of the time, it’s a bit too simplistic and there are many exceptions. The main exceptions have to do with the fact that we adjust our saddle height based on the amount of knee extension at the bottom of the pedal stroke, or the 6 o’clock position. This is fine most of the time, but due to individual differences in body measurements and mechanics, you can have your saddle height adjusted perfectly for the amount of knee extension at the bottom of the stroke and still have too much knee flexion at the top of the stroke.How? One way is by having incorrect crank length. Regardless of crank length a rider can always get the proper amount of knee extension at the bottom of the pedal stroke -- this metric, how straight the knee is at the bottom of the pedal stroke, is looked at in bike fits the most. What is often ignored however is how much knee flexion occurs at the top of the pedal stroke. The longer your cranks are, the more your knee will be bent at the top of the pedal stroke. So what’s the right length for you?Crank length is a fractious topic and diving into the research to come up with a cohesive explanation would require an entire book unto itself. If I were to boil it down to three simple ideas, they would be:
Power generation is independent of crank length -- you don’t get more power by simply having longer crankarms
Most research shows that wildly varying crank length (from 140 mm or shorter all the way up to 210 mm and longer!) doesn’t have a dramatic impact on many measurable variables of mechanical efficiency (or power of course) at least in the short term
There’s no evidence that having cranks that are too short make you prone to injury, but having cranks that are too long can certainly create problems for some.
cycling knee pain
As for determining what your proper crank length should be, there are some formulas where you can plug in different measurements like your inseam, tibial length, overall height etc, and come up with an optimal crank length. But as with most formulas, they have severe shortcomings and fail in exactly the area we’re trying to succeed -- accounting for individual differences and when someone doesn’t “fit the mold”.
The best way to determine whether you have the right length cranks is exactly the same as trying to find the right saddle height -- it helps to measure it. Again, you can refer to my past videos on getting the right saddle height (link to 100-, 200-, and 300-level articles), whether they be the simple ones, the heel on pedal test, or advanced, where you can take yourself through a basic video motion capture assessment. After doing any of these tests you make appropriate changes to your seat height and riding for a few weeks proves to be less painful, but the symptoms have not completely resolved after a few weeks you’re still experiencing the same (or worse) knee pain in frequency, intensity, or duration, then it might be time to explore crank length.
I'd encourage all riders to take advantage of a free program I have outlining how anyone can measure relevant joint angles while pedaling on digital video. Again, this program is free just by simply signing up on my website. This represents a more advanced method of personal bike fitting that can make help a rider learn a ton about themselves and how they sit on and interact with their bike.Let's assume you perform this advanced method and through the data you accumulate, you decide to raise your saddle up and get your knee extension into a better range especially for the tissue at the front of the knee. Now that you’ve optimized your saddle height for knee extension at the bottom of the pedal stroke you can then check those same videos to see what the maximum knee flexion angle you have towards the top of the pedal stroke. If your knee extension at the bottom of the stroke is good, but flexion at the top is getting pretty close to the limits of where we like to see most people and, most importantly, you still have knee discomfort, then you may be a good candidate for shorter cranks.
Another, less common, cause of too much knee flexion is using a shoe/pedal combination that has too much stack height. What is “stack height? It’s the distance between the bottom of your foot and the center of the pedal axle. The thicker the sole of the shoe and the higher the engagement surface of the pedal is from the pedal axle, the more stack height a rider will have. Imagine if you wear running shoes on platform pedals -- the combination of the thick sole of the running shoes with the large platform pedal body could put the bottom of your foot a significant distance from the center of the pedal axle. The same can happen even with clipless pedals which all have varying amounts of stack just as all cycling shoes have different amounts of sole thickness.What about saddle fore/aft?
In the debate about front of the knee pain, along with saddle height some will mention that having your saddle too far forward is also a culprit, and this is sometimes a valid point. But this is another area where it’s not that simple. If you take a rider that has a properly adjusted saddle height and you simply slide their saddle forward on the rails of the seatpost, this WILL put more pressure on the front of the knee largely because when sliding the saddle forward you are also lowering the overall height slightly as well because of the 72-80 degree angle of the seat tube. But if you adjust for saddle height when you slide the saddle forward, by raising it a few millimeters, knee extension remains the same at the bottom of the pedal stroke and the knee flexion at the top of the pedal stroke stays the same as well -- the hip and knee are just in different locations but the overall triangle between the Hip → Knee → Pedal remains unchanged because the saddle height remains hasn’t changed nor has the length of the upper and lower leg. In most circumstances this won't cause knee pain by itself.Having the seat too far forward, even with a properly adjusted seat height CAN create extra stress on the patellar and quad tendons.
How? When the seat moves farther forward the hips move as well, so they end up being closer to directly over the bottom bracket (and feet) rather than behind them. With the hips further forward, and the upper body in a standard road bike position, it’s more difficult to engage the hip extensors, which are the large gluteal muscles in our rear end. The hip extensors work best when the pelvis is in a stable position. When our hips get too far forward, we lose the stability of the pelvis because we lose some of our stabilization through our feet.
Newton’s Second Law and your bike seat
cycling knee pain
cycling knee pain
If we look at a cyclist from the side, their hips sit behind their feet during the power phase of the pedal stroke. And at all times, the hips are above the feet, because our saddle is above the cranks and pedals -- pretty basic, right?
When we push on the pedals during the power phase of our stroke the pedals are pushing back. Newton’s Second Law of Motion is the one that has the “equal and opposite reaction” clause in it, so not only are you acting on your pedal, your pedal is acting on you as well. Because the pedal is below your hips/pelvis, when you push down on it, it’s pushing back up on you (and your pelvis). This is great because it provides, among other things, a brief period of unloading of pressure on the saddle -- it literally saves your butt during rides. This is why one of the largest segments of riders plagued with severe saddle issues has partially to do with their lower power output relative to their body weight. If your power to weight ratio is poor you’re not going to be un weighting the saddle much.Because the pedals are in front of your hips/pelvis during the power phase, when you push down on the pedal, the pedal is also pushing you backwards on the bike. This exerts an aft or posterior force on the pelvis which provides stability by keeping it securely in place on the saddle instead of sliding forward.When the hips stay backwards on the saddle, the hip extensors have a solid platform to push from. When the hips slide or roll forward during the pedal stroke (because the seat/pelvis is not far back enough behind the pedals/feet), the fact that the pelvis is moving keeps the hip extensors from working at their full level.When the hip extensors don’t work as much, or perhaps they’re delayed, it requires the quadriceps to work more and this extra work and force is passing through the quad and patellar tendon.
Another pitfall to having the saddle too far forward
cycling knee pain
Something I’ve noticed in my bike fitting practice is that having the seat too far forward can also lead to a more toe down posture at the ankle. Pointing the toes more causes the leg to act longer which bends the knee more. You can do this on your own bike….with your foot on the pedal lift the heel and point the toes more and watch what happens to your knee -- it bends the knee more, right? The compensation of pointing the toes is the result the body trying to improve stability for the rider. In the standard road position we have good stability when the hips are behind the feet (when the saddle is pushed more aft -- see the paragraph above regarding Newton's Laws). When the saddle is pushed forward, the hips will be closer to being directly over the feet. This creates a scenario where the rider will not be balanced on their seat and a disproportionate amount of weight falls forward onto the hands.
Pointing the toes creates some artificial stability through the feet by putting the balance point for the foot on top of or in front of the pedal which exerts a force either up or back respectively on the rider. It’s basically an effort to get the feet more in front of the hips, because pedaling with the heels dropped puts more of the foot behind the pedal and therefore further underneath the hips rather than in front of them more.When I see athletes in this ‘too far forward’ saddle position and I move their saddle back, often they begin to naturally correct their toe-down posture after just a couple rides. This allows the knee to extend normally and takes the strain off the front of the knee structures.
Possibly even more important is that being in a toe-down posture also has the effect of preferentially activating the quadriceps over the hip extensors/glutes. When the quads work more, we have more force going through the front of the knee.We can see a great correlation to this in terms of proper squatting technique. Many people squat incorrectly and let their weight move forward onto their forefoot and toes -- this causes the knees to track in front of the knees during the squat. Ideally we want to keep the weight on our heels and midfoot, which will keep the knees predominantly behind the toes, and the hips back. This allows the glutes and hip extensors to get in the game and do their share of the work. On the bike, we can’t exactly push through our heels, but as we minimize the amount that we’re pushing through our toes and forefoot (by not toeing down), and keeping our hips behind our feet, we get more engagement from our hip extensors. The result is better balance between the muscle groups, and less force and compression moving through the kneecap.
Cartilage under the Patella
cycling knee pain
Mechanics of Injury
Cartilage is an interesting tissue. It acts like a slippery surface to ease the motion between two joint surfaces. It often has curves and contours to help guide the motion at the joint by allowing the two ends of the bone to mate perfectly. It’s fed by synovial fluid and at the same time the synovial fluid acts as the lubricant to make the joint motion smooth and resistance-less.The cartilage under the kneecap is no different, in that it fills the gap between the two round surfaces of the femur and facilitates the movement of the kneecap as it moves up and down in this groove in order for the knee to bend and straighten.
The kneecap itself acts as a fulcrum point to increase the transfer of force from the quads in the upper leg to move the lower leg and straighten the knee. It’s called a sesamoid bone and we have a number of them throughout the body, although the kneecap is the largest.Since the job of the entire quadricep complex is to straighten the knee, we can assume it does a lot of it’s work with the knee bent. With the knee bent and the quad tightening, the kneecap is pressed into the femur as it glides up with the straightening of the knee. Just as we saw with the patellar tendons, the more the knee flexes during the loading phase when we’re pushing down on the pedals, the greater the amount of force the patella is pressed into the femur which can lead to damage or irritation to the cartilage on the back of the patella. So the cartilage experiences a compression injury. At the top of the pedal stroke if the knee is flexed 120° or more, the kneecap is literally being jammed into the femoral groove.It’s no big secret what the most common way to have increased flexion on the bike -- having the saddle too low. All the same fixes apply -- raising the saddle, moving the saddle aft, and/or shortening the cranks.Pain under the kneecap is one injury that responds especially well to shortening crank length. I’ve found that some cyclists are particularly sensitive to knee flexion under force at the top of the pedal stroke and shortening the crank can almost completely solve the problem on its own.What if none of this works?
Sub-patellar pain can be extremely stubborn and in some athletes it can progress to an advanced chronic level where it’s called chondromalacia patellae. It can persist even when saddle height, fore/aft position, and crank length have all been optimized. This program is not meant to be a substitute for medical care, so if you’re in this camp, you can visit your favorite PT and they can get you set up with specific exercises to treat this persistent problem.But we haven’t exhausted the bike fit solutions just yet. The kneecap is often acted on in a non-linear way. It doesn’t move much side to side because of the way it tracks in the groove at the end of the femur and numerous things can exert medial (to the inside) and lateral (to the outside) forces on it and create excessive pressure on different aspects of the sub-patellar surface. For this reason, there are a number of solutions in the coming modules that explore medial and lateral knee pain that can affect the cartilage of the kneecap. These coming modules address medial and lateral knee pain and often these fixes can provide support for sub-patellar issues as well.IT band is often blamed for pain on the outside of the knee, and while I usually don’t ascribe to generalizations in bike fitting, but there’s just not a whole bunch on the outside of the knee.
Medial and Lateral Knee Pain
cycling knee pain
The outside, or lateral, and the inside, or medial, aspects of the knee are very common areas of trouble for cyclists, second only to front of the knee problems. The lateral side of the knee might be the simplest to understand in terms of the structures involved that can create discomfort, because the truth is, there just isn’t a whole lot on the outside of the knee. The medial side is slightly trickier but we’re going to break things down in a very simple way
Lateral Culprits:
IT Band
Lateral joint ligaments of the knee
Lateral Meniscus
Medial Culprits:
Medial Joint Ligaments
Pes Anserine Area
Medial Meniscus
We’re going to address the knee joint ligaments, medial and lateral, together because these structures are injured by the same movements -- often in the opposite direction, but the same movement nonetheless. We’ll do the same with the medial and lateral meniscus.
Ligaments of the knee -- these are the structures that provide more ligamentous support for the knee joint and also hold the kneecap in place. We often think of the major ligaments of the knee, like the anterior cruciate ligament (ACL), medial collateral ligament (MCL), and lateral collateral ligament (LCL) as very defined bands of tissue in and around the knee. And in the case of the ACL, this is true -- it’s a very distinct strand of tissue in the knee joint. But the LCL and MCL are both more vague structures because the are part of the greater joint capsule surrounding the knee. This joint capsule is a patchwork of thin tissue plastered in a ball that completely surrounds the knee joint. The LCL and MCL are just thickenings on either side of the knee joint -- where the ligament ends and the capsular tissue begins is a bit of a gray area.Because of this, defining exactly when the irritation happens on the LCL versus another tissue isn’t usually a useful argument to engage in -- we can just discuss them as a whole by saying there is a problem with the ligamentous structures on the lateral side of the knee. We will treat or manage these issues the same way.Ligaments are irritated in much the same way on either side -- through varus/valgus forces and torsion of the tibia (see below).The IT band and lateral retinacular ligaments often go hand in hand because the IT band actually has a few fingers of tissue that attach to the lateral side of the knee cap, so often symptoms from the IT can also come from lateral retinacular ligaments and vice versa.
Lateral Meniscus: The meniscus is cartilage in the knee joint which allows the round end of the femur to mesh with the flat surface of the tibia. Both meniscii (medial and lateral) are adhered to the top of the tibia.The lateral meniscus is injured less often than the medial, but both are irritated mainly through compression. The reason the meniscii are less problematic on the bike is because pedaling a bike creates much lower levels of compression than other activities, like walking, running, or jumping. So generally, if a rider has meniscal damage and irritation, riding the bike is usually much more comfortable than other activities. Essentially, if you have enough meniscal damage to create pain on the bike, you probably have larger problems you need to address and so it may not be useful to search out significant gains through bike fitting.
Mechanics of injury
The mechanism of irritation for medial and lateral problems includes torsion of the tibia on the femur, and varus/valgus stress on the knee joint.Think of torsion as the tibia rotating along its length, like when we pivot too quickly and we twist our knee joint. Some degree of tibial torsion is normal -- the tibia needs to rotate in order to allow the knee to flex and extend fully. On the bike, because we have rapid knee flexion and extension, the amount of this torsion motion needs to be tightly controlled to avoid straining the tissue surrounding the knee and creating irritation. This becomes especially important with our feet clipped into the pedals. A poorly positioned cleat might be able to exert enough force on the tibia to twist the knee as it flexes and extends during pedaling and irritate the surrounding knee tissues.
Varus/Valgus: These two forces are often new to people, but they’re really simple to understand. Picture the knee straight and a force pushing on the knee joint from the medial side, pushing it laterally into a bow-legged posture -- this is varus movement. A force pushing from the outside on the knee into a knock-kneed posture is a valgus force. Knees don’t normally bend this way of course, but squatting or pedaling a bike (any activity that involves bending the knee with the feet attached to something be it a pedal or the ground) there is the chance of introducing a varus or valgus force.I want to reinforce that it's not necessary for you to have an anatomical varus or valgus knee deformity -- usually known as being bow-legged and knock-kneed respectively. A force that pushes on our knee laterally to the outside as a varus force, or a force pushing it medially as a valgus force can create problems.Where to look for these forces? What causes torsion and varus/valgus forces? Let's look at the most common ways that these forces are introduced to the legs.
Q-factor
cycling knee pain
Q-factor can be thought of as the stance we have on the bike. Essentially how far apart our feet are when they’re on the pedals. Some bikes place the feet closer together (narrower q-factor) while others will place them further apart (wider q-factor).It’s important to not confuse q-factor with q-angle. We know what q-factor is now -- q-angle has to do with the knees and the angle in the frontal plane that the femur and tibia come together at, and, incidentally can have an effect on what we just talked about in varus and valgus knee deformities.
For example, some women have wider hips, which causes the femur to angle down and in (when viewed from the front) and then the tibia angles down and out to the side creating an angle where the knee sits to the inside of the hip and ankle in a knock-kneed posture. If you’ve been paying attention you’ll see that this posture exerts a valgus force on the knee.Even if our q-angle is normal, having a q-factor that’s not appropriately matched to us can create a varus or valgus stress on the knee.In this scenario the feet are out of line with the hips. For instance a very small rider with narrow hips is riding a standard road bike that otherwise fits well. But the bottom bracket width, combined with the stance of the cranks and the length of the pedal spindle, puts her feet outside, or lateral to, her hips. This can create a valgus force (knee is pushed in toward the bike) on the knee and put strain on the structures on the medial side of the knee.The opposite scenario is more common as many riders have a q-factor or stance width that’s too narrow, so the pedals sit too close to the frame given the width of their hips. Lateral knee discomfort is more common in this situation as there is a varus force (knee is pushed out or away from the bike) being applied to the knee. But if the mechanics of the feet are compensating by rolling the ankle (and midfoot) inward, medial knee pain is still possible with too narrow a q-factor or stance width.
Measure/Visual: The small rider with the too-wide stance will look like they pedaling with their knees heading in toward the top tube. In fact if we trace the knee path we’ll see the knee drift toward the top tube at the top of the stroke and move down and away from the midline of the bike on the downstroke.The rider with their feet too close together will have their knees moving away from the midline of the bike at the top of the pedal stroke and toward the bike on the down stroke. Knees moving up and out. Again this is the more common situation.
Rider Report: The too-wide, “up and in” riders will often complain of medial (inside) or posterior (back) knee pain, but lateral discomfort is possible. Because of the cascading effects of the biomechanical chain, there also might be pain toward the inside of the foot --perhaps around the big toe.The more common scenario of the rider with too narrow a stance on the bike will have lateral knee pain as the varus force is acting on the knee. The rider might also complain of pain on the outside of the foot if their ankle and midfoot flexibility is on the more restricted end of the spectrum. If, however, they’re more flexible through the ankle and midfoot, they too can have pain on the inside of the foot, near the big toe. The lateral knee pain can go along with IT band discomfort so it is possible for them to experience lateral thigh or hip discomfort extending all the way up to the pelvis and SI joint.
Bike Fit Fixes (again, more depth on this later, but here's just a taste)
Addressing q-factor issues isn’t terribly difficult since many/most cleat and pedal systems allow the for adjustment to widen or narrow the stance of the rider. Usually small adjustment are all that are necessary. It’s important to think in opposites when moving the cleat though as many riders get confused. When looking at the bottom of the shoe at the cleat, you need to think in opposites: If you want to move the feet out to the side to create a wider stance, you need to move the cleats in towards the inside of the feet. Incidentally, same goes for rotation of the cleat -- we still need to think in opposites and if we want our foot to toe out more we need to toe the cleat in, and vice versa.Some pedal systems don’t allow for any medial/lateral adjustment however -- like some versions of the Time ATAC mountain bike cleats. Most pedals do allow for this adjustment -- LOOK Keo, LOOK, Shimano’s SPD-SL, Speedplay, Shimano SPD, TIME road pedals, some versions of Crank Brothers Egg Beaters and some versions of TIME ATACs. If your pedal system doesn’t let you do this, your options are a bit limited:Change pedal/cleat system -- this isn’t terribly economical but not a bad option since there are so many options and finding a reasonably inexpensive version is possible.Find a crankset that has a wider or narrower q-factor spacing -- this is not recommended since finding a crankset with a wider stance can affect the shifting performance of the bike by messing with the chain line. And new cranksets aren’t cheap.Get pedals with a longer or shorter spindle. Some pedal manufacturers offer aftermarket spindles of various lengths, most notably Speedplay. But Speedplay already has medial/lateral adjustment built into the cleat so it may not be necessary. File that under “If you need more medial/lateral adjustability”. New versions of Shimano Ultegra pedals are also available in "+4 mm".There are spacers that can be added between the crank and the pedal to increase the stance width. Bikefit.com offers a 20mm spacer, which is quite a big change, but due to how it is assembled is only compatible with pedals that have wrench flats on them - something that’s becoming increasingly rare these days as most pedal makers use an 8 mm allen key on the end of the spindle for installation/removal.
Forefoot Wedging/Posting
cycling knee pain
Besides addressing the stance of the pedals another common bike fit adjustment that needs to be made in conjunction with it is posting the forefoot for varus/valgus. There are those words again -- varus and valgus. Think of this as tipping the foot so that it's either oriented with the inner edge of the foot (and big toe) lifted up (forefoot varus) or with the outer edge (little toe) lifted up (forefoot valgus).For the rider that has their feet set too narrowly, along with moving the cleat position to increase the stance width (or longer pedal spindles if you want a more aggressive fix), often a bit of varus posting of the forefoot can help. Especially if the rider has normal to flexible foot and ankle mobility, this can help to stabilize the foot so that the knee can track more vertically and relieve movement through the hip.We can add varus forefoot support by placing wedges under each cleat or under the foot itself inside the shoe. They are also sold by bikefit.com, but there are other options available from Specialized and Shimano.
These wedges are pretty simple, and in order to get varus support, place the fat side of the wedge to the inside of the foot. I should note that in my bike fitting practice, I don’t use these shims very often -- perhaps in 20% of bike fittings. When they’re necessary, they can be very helpful and a little goes a long way. In most cases, just two wedges are often enough to have an impact. I do use more on occasion but it’s very rare -- I’ve seen many riders come through my door with some very tortured cleat wedge and shim combinations that often end up being entirely unnecessary.Most people respond to varus support -- about 75% of the population exhibits natural forefoot varus (although they likely won't have symptomatic clinical forefoot varus deformity), and this seems to correspond well with those responding to forefoot varus support on the bike.
Symptomatic forefoot varus is reasonably rare, but cyclists tend to respond well to mild varus support likely due to the low weight-bearing environment that cycling presents.With so much of the population having natural forefoot varus, many bike fitters want to post almost everyone that comes through their doors. But the truth is that most people are asymptomatic -- they may have forefoot varus posturing but it's either not severely postured, it doesn't move dynamically enough to create a problem, or, as is often the case, the cycling shoe itself already has varus posting built into it. In these situations, mild posting of the forefoot with wedges, perhaps just two, often doesn't create a problem, but it's also not performing any real function. I see this scenario often -- it's hallmarked by seeing no change in pedaling mechanics when we remove them.
Insoles
There will be cases where a custom or semi-custom insole will be the best solution for the rider. Because of the extra space that the insole requires, a new pair of shoes may be necessary, so this isn’t a cheap solution, but it may be the best solution especially in very stubborn cases of a forefoot varus that is creating problems. Having the ability to control the posture of the heel and the midfoot, which you don’t get with the cleat wedges, can be critical to establishing a solid base for the leg to work from.
The overly flexible cyclist and medial/lateral knee pain
Flexibility is often seen as this overwhelmingly positive trait, and in many respects it is a very good thing. But there is a misconception that cyclists (or runners or triathletes) always need to be more flexible. The truth is that in order to be a healthy, uninjured cyclist only a small amount of flexibility is fundamentally required. Having a little more than that is good. Having a lot more than that isn’t better -- and it can often lead to trouble.I have many clients, often women, who are already very flexible and yet they still focus on their yoga or flexibility training on a daily basis. (Many athletes gravitate toward what they’re already good at, so those already with above average mobility default to yoga or stretching since it comes so easily to them).The other side to the “too flexible” coin is that the athlete doesn’t have enough strength or stability. This lack of stability can lead to aberrant motion at the spine, hip or knee during the pedal stroke.A very common presentation has the knee drifting medially or laterally because of poor stability through the hips which can lead to knee pain on either side. This is a situation where the rider would benefit from being less flexible as a bit less freedom of movement through the spine, pelvis, and hips can provide some passive control for the lower extremity, and especially the knee, as it goes through the pedal stroke.Another factor to consider is the type of pedal system the cyclist is using. Most pedals have very similar amounts of freedom of movement, called “float” -- TIME, LOOK, SPD-SL, SPD all live in the 3-9 degree range which is in line with what most athletes require. During my bike fittings many athletes are surprised to learn that more often than not we use somewhere between one and four degrees of float.
Speedplay pedals, however, can have nearly 30 degrees of float available to the rider. For some cyclists this can be a good thing -- these are generally cyclists with poor overall flexibility and the added float allows the hips to move through their limited available range without restriction (the feet “floating” are allowed to move to relieve this movement). Interestingly many of these riders also don't use excessive amounts of float which begs the question of the whether it's the float that relieves their problems or some other characteristic of the pedal.In my experience, the way Speedplay pedals affect riders breaks down like this:~15% really benefit from the significant float since the freedom of movement works well with their sometimes less flexible frames~15% the extra float actually causes them problems. Often these riders have above average flexibility and mobility and perhaps lack some stability through their body.~60% of riders, they make no difference positive or negative. For athletes with average mobility these pedals don’t create too many problems, but the extra motion isn’t necessary or used in any functional way.Cyclists already too flexible can have big issues with them because the “too flexible” cyclist also has limited stability so they are unable to control all the freedom of motion that the Speedplay pedals leave them with. There are variations of Speedplays that allow you to limit the amount of float, but usually any of the other pedal choices that have more standard amounts of float will work well. The lack of float creates some stability for the rider since their muscular stability is limited
Measure/Visual:
Overly-flexible cyclists will display knee medial and lateral motion as seen in other situations -- the clues to the real problem will be discovered during the off-the-bike physical assessment of the rider. They will score well above average in testing for hamstring length, and especially hip internal and external rotation. When I have a cyclist with 20-45 degrees of hip rotation in both directions I begin to think that they might run into problems with stability or control of hip motion. Having this flexibility certainly doesn’t guarantee there will be a problem -- excellent athletes are hallmarked by exceptional flexibility that is controlled well by adequate muscular stability -- but if issues do arise then stability needs to be addressed.
Rider Report:Complaints aren’t terribly unique. Often the rider looks at their flexibility as a good thing (and they double down on it and work on it further as mentioned before) and so they won’t recognize it as the source of their problem. It is possible, due to all the uncontrolled movement, for the knee pain to occur on both sides and pain in other areas, especially the hip and low back is common, since the aberrant motion is transferred.Aside from that there is nothing very unique in the subjective complaints of the rider.
Bike Fit Fixes:If an overly flexible rider is using Speedplay pedals, then either limiting their float or changing to another pedal system can create some stability to control hip and knee movement. Many times this is enough, but my recommendation for most athletes, even if this is successful is to not stop there. Stability training and exercises are the best way to permanently solve the problem. There will be more on this in future installments.
Too Much Toeing Down
Too much toeing down or pointing the toes is another common driver of knee pain. It has the distinction, however, of being able to cause knee pain through the anterior structures, like the patellar and quadricep tendons, but also through medial/lateral structures as well.Cyclists often toe-down, or point their toes, during their pedal stroke when their saddle height is placed too high. In an effort to reach the pedals easier, the toes are pointed to make up some distance. Usually the knee is already extending, or straightening, further than it should be from a functional movement standpoint and the effectiveness of the pedal stroke is diminished.
Certain aspects of a poor bike fit, like cleats being too far forward or the hips being too far forward relative to the rider's feet can facilitate a toe down posture. A major struggle with any sort of ankle or foot mal-alignment is that even when the bike fit is fixed, the ankle and foot are very slow to change. I call them slow adapters. I believe the ankle and foot are slow to adapt because a lot of their influence is in the area of proprioception and balance which are very primitive and basic body functions that are managed in lower brain centers of the brainstem. These primitive tasks can get quite hardwired into us and it makes sense that they might take time to change.
An ankle/foot toeing down more will create more knee flexion throughout the pedal stroke. The more we plantarflex the more our knee will be bent. THis increase in knee flexion can lead to more force being placed through the front of the knee as described numerous times above.Something else can happen though to create lateral knee pain. Especially when the saddle is a little too high and the ankle is/foot is pointing to reach the pedals easier, as the foot points down, there can be a tendency to invert the foot as well as an enhanced torsion (twist) of the tibia. When the tibia rotates excessively it can pull on the IT band that inserts on the lateral side of the knee and create knee or hip pain. This is one very common way riders experience IT Band discomfort on the bike
Next Up: Bike Fit Fixes - what changes can be made?
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Real World Example Bike Fit #1