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I see bantered about on the forum that singlespeeding is hard on the knees, is this really the case? As a retired paratrooper with the notoriously bad knees that go with that line of work, I haven't noticed any more knee pain than usual in the little less than a year I've been riding a SS. How about the rest of you guys?
 

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I have always ridden bigger gears on my geary bikes both on and off-road and have been SSing for 2 years now with no problems. I have friends who use smaller gears on their geared bikes that occasionally suffer from knee problems. I don't think mashing bigger gears necessarily means you are going to have problems but if you have dodgy knees caused by other activities, it may make it worse.
 

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I've got one F'd up knee from high school football that sometimes comes back to bite me in the A. I've only been SSing for a little over a year, and I've stepped up my riding in the last couple of months to almost daily and I have not had any problems(yet) with my knees while on the trail or immediately after.
 

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knee pain

As a PT and someone who has performed hundreds of bike fits and rides a SS many times a week and commutes on a fixie, it is my strong opinion that it will not cause knee pain. What does cause knee pain on any bike is a poor position. Could be too high, too low, but poor setup causes excessive compensation in other planes of motion which torque the kneee excessively. Proper setup will eliminate this from happening all together.
Is SS more taxing at times? sure - you might get more sore on occasion, but as far as damaging the structural integrity of the joint lining, I do not see any direct problems. The knee is a wonderful structure and set up to withstand a lot of load in its normal operating range of motion.
 

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At my size, my knees have traditionally bee more sensitive to things. Improper fit, for sure, over-use, all of it. Never, though, has SSing been at fault. Even at the end of the Vision Quest each year, when I've pushed the SS over 12k vertical feet over 60 miles...the knees don't hurt....Granted, everything else does!

FWIW, my wife suffers from an acute case of IT Band Syndrome. She's been doing PT for at least 1 year to combat it. Riding her single is the time her IT hurts the least.
 

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jayoutside said:
As a PT and someone who has performed hundreds of bike fits and rides a SS many times a week and commutes on a fixie, it is my strong opinion that it will not cause knee pain. What does cause knee pain on any bike is a poor position. Could be too high, too low, but poor setup causes excessive compensation in other planes of motion which torque the kneee excessively. Proper setup will eliminate this from happening all together.
Is SS more taxing at times? sure - you might get more sore on occasion, but as far as damaging the structural integrity of the joint lining, I do not see any direct problems. The knee is a wonderful structure and set up to withstand a lot of load in its normal operating range of motion.
Here is a question with respect to your professional opinion on fitting and further information sources.
Background: I experienced a case of chondromalacia in the early '80s after getting a new road bike and putting on massive miles that year. The causative factor was most likely a poor angle on the old-style nail-on cleats in use then (anyone remember those?).
My question is, what reading can I do regarding the affects of both seat height and fore-aft positioning. In positioning height, I have always used the rule of thumb of a 5-10 degree bend at the top of the pedal stroke. In fore-aft posisioning, I have used the rule of getting the kneecap over the pedal spindle with the crank in the 9 o'clock position. These have served quite well.
Thanks for your input. Any references to articles, books, or web-info will be appreciated.
Keep on SSÃ*ng!
 

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Potential Roadkill said:
I see bantered about on the forum that singlespeeding is hard on the knees, is this really the case? As a retired paratrooper with the notoriously bad knees that go with that line of work, I haven't noticed any more knee pain than usual in the little less than a year I've been riding a SS. How about the rest of you guys?
I think it depends on your knees, and what the problem is with them. I have heard many people say it has actually helped their knees. I am not so sure about my own, though. I was a little hesitant to try ss'ing because my left knee gets a little gritty feeling when I would stand and push a high gear on my geared bikes too often. And now I find that if I ride the ss too much the knee begins to feel the same way. I really enjoy the ss experience, but I may have to call it quits for the sake of my knee.

I'm no doctor, but I think if it feels OK then it is OK.

Kapusta
 

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Potential Roadkill said:
I see bantered about on the forum that singlespeeding is hard on the knees, is this really the case? As a retired paratrooper with the notoriously bad knees that go with that line of work, I haven't noticed any more knee pain than usual in the little less than a year I've been riding a SS. How about the rest of you guys?
Only if you are stupid. If you insist on running a big gear, rarely stand to pedal and/or never getting off the bike and pushing you may have knee problems.

If you listen to your body, hop off and walk or run up the steeps on occasion Your knee will not only be less likely to hurt, you will be making them stronger. Cross training is good!
 

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My knees have been really abused for years...and I do mean really_abused.

Riding singlespeed has helped my knees and my leg muscles get stronger. I don't sit and pedal much though, I am normally standing up and pedaling on the SS.

Also, here's something to consider...

Technique : I found that I was having problems with my leg muscles and a bit of knee pain for a while, and traced it down to very bad technique when standing and climbing on the singlespeed.

You really have to let the bike move around a LOT when you are working hard up the hills.

The action of pulling up hard on the handlebar as you push down hard on that same side pedal is very important. The bike has to sway from side to side in quite a wide arc beneath you so you are getting a nice straight push downwards on the pedal with no deformation or twisting of your leg and knee.

I had to practise it by over-exaggerating the action for a couple of weeks to get it re-locked into my muscle-memory properly. Also, I use platform pedals so that I can align my feet on the pedals more easily. I found that being clipped in prevented me from attaining the positions on the pedals that I was really comfortable with.

Since doing that, I have had no more problems with any pain at all.

All singlespeeding has done for me is to make my legs and knees stronger.. :)


R.
 

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Rainman: The action of pulling up hard on the handlebar as you push down hard on that same side pedal is very important. The bike has to sway from side to side in quite a wide arc beneath you so you are getting a nice straight push downwards on the pedal with no deformation or twisting of your leg and knee.

I am not sure I agree with this. Perhaps this is necessary with platforms, but with clipless you can greatly reduce the downward force by using your other leg to pull up on the pedal. This requires a more disciplined spin with somewhat reduced swing. The result is an easier overall effort. And pedals such as Crank Brothers give you tons of float for ideal allignment.

The minute you find yourself pulling real hard on the handlebar, you are exerting a lot of force on the knee. Effectively you are doing one-legged half squats with more than you body weight. Nothing wrong with that if you have the conditioning for it. Unfortunately many people hit that "body english" stuff without the strength training and conditioning required. The knees need time to build up to that type of effort.
 

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I'm no doctor, but I see people on geared bikes whose knees I worry about much more than those who ride a singlespeed. Most of the time on a single, you're spinning like a hamster on crack, with a very light load on the knee, and a fast leg speed -- this is good! The uphill grunts do place a load on your joints, but as others have offered, the increased fitness that SSing will give you should help to mitigate injury. I recommend that you take it easy for the first several months of singlespeeding until you build up a good, solid base of relatively flat miles. What scares me are the guys on their multispeeds who never get out of the big ring, and mash away over even flat terrain. Seems to me that the long-term effect of long-term big-gear mashing will be far more devastating that the spinning inherent to riding a 1 x 1.
 

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I've noticed that my "bad" knee feels more stable now that I've been almost exclusively singlespeeding for a year. I think it's due to a couple of reasons:

1) The muscles that cross my knee joint are stronger than they used to be, and I theorize that it has reduced the burden on the ligaments to stabilize the joint.

2) When the knee is flexed, the joint "unlocks" and the tibia can rotate slightly upon the femur. When the leg is straight however, the joint "locks" and there is no rotational movement.

A) On my powerstroke, I'm more often standing up and my leg is straighter (knee joint is closer to 180 angle) than when seated, and therefore more anatomically stable when under load.​

B) When I sit and spin on a geared bike, the powerstroke happens when my knee is more flexed than when I stand, and is therefore less anatomically stable and more likely to stress the ligaments. Due to lower gearing the load with each downstroke is much less than when standing, but it happens repeatedly.​


I consider myself a masher, not a spinner, so I have relatively low RPM's versus when I'm geared. On flat terrain though, I spin out just like everbody else. On a geared bike, if people mash while seated, I think this is when damage can happen. In my recollection I've hurt my knee when mashing a big gear seated, but never when standing.

Maybe pushing big gears seated is the big villain? Maybe the body can tolerate a repetitive, higher load against a stable knee more than it can a repetitive, lighter load against a slightly unstable knee?
 

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serious said:
The minute you find yourself pulling real hard on the handlebar, you are exerting a lot of force on the knee. Effectively you are doing one-legged half squats with more than you body weight.
Yes, you are exerting a lot of force on the knee, but the leg is straight or nearly straight, not flexed as in a squat. Please see my other post below to further this discussion.
 

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serious said:
I am not sure I agree with this. Perhaps this is necessary with platforms, but with clipless you can greatly reduce the downward force by using your other leg to pull up on the pedal. This requires a more disciplined spin with somewhat reduced swing. The result is an easier overall effort. And pedals such as Crank Brothers give you tons of float for ideal allignment.

The minute you find yourself pulling real hard on the handlebar, you are exerting a lot of force on the knee. Effectively you are doing one-legged half squats with more than you body weight. Nothing wrong with that if you have the conditioning for it. Unfortunately many people hit that "body english" stuff without the strength training and conditioning required. The knees need time to build up to that type of effort.
This is true, and I agree up to a point.. I wasn't advocating platform pedals for everyone, only saying that they suit me and the way I like to ride. I agree that clip-ins are more efficient generally.

My riding has evolved to it's present state over a period of years..off and on mountain bikes. I am by no means an authority...lol..quite the opposite. What I wrote was probably badly put.

In retrospect, the force I exert on the driven pedal is aided a lot by body-weight as well as muscles. This is a good reason for swinging the bike from side to side, it places all your body weight right over that pedal and helps you push it downwards. It's called..standing and "mashing".. :)

My post was more related to those long hard uphill grinds where your momentum is almost gone, you are working hard just to keep going uphill against gravity. I dont "spin" in these situations, I "mash" ........ and grunt. :)

Yes, it does take a certain amount of fitness, but I still maintain that correct technique goes a long way in preventing injury.


R.
 

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To clear things up

So here is a few things in case people want some honest explanation based on anatomics and biomechaincs. Not trying to create turmoil, just help clear up a few things. I don't even know Nat, but I'm using Nat's post as an example since he raises some common concerns and thoughts:

1) The muscles that cross my knee joint are stronger than they used to be, and I theorize that it has reduced the burden on the ligaments to stabilize the joint.

RESPONSE 1: this is probably true although 2 seperate things are happening here. Cycling is predominantly done in one plane (sagital plane). The majotiry of the motion at the hip/knee/and ankle serves to drive te pedals around in the sagital plane and make you go all kinds of places on your bicycle. Is there any motion in the other planes (frontal and transverse)? Yes there is. Some very small motion in these planes is compensatory and necessary, most of this motion however causes most of the problems we see in cycling. The body is not set up to stabilize all this motion which creates stress and strain in area the body is not able to support (chondromalacia, ITB syndrome, patellar tendonitis, quad tendonitis, etc). So while cycling definately stregthens your ability to propel yourself in the sagital plane, it also increases your ability to control and stabilize motion in other planes.

2) "When the knee is flexed, the joint "unlocks" and the tibia can rotate slightly upon the femur. When the leg is straight however, the joint "locks" and there is no rotational movement."

RESPONSE 2: big problem with this statement and I think you may have heard this the wrong way. Yes, it is true that when fully extended (0 degrees or into hyperextension) the knee goes into a "locking" position called the "scewhome mechainsm". Basically, what happens at this point is that the femur and tibia rotate on each other to increase the congruency of the joint surface and lock the knee. So yes, this happens, but its more like an on/off effect. As you approach this 0 degree locking point, the knee does not become more stable as stated. Its either locked or not locked. Its an anotomical thing. The knee is no more mechaincally stable at 3 degrees than it is at 40 degrees.

B) " When I sit and spin on a geared bike, the powerstroke happens when my knee is more flexed than when I stand, and is therefore less anatomically stable and more likely to stress the ligaments. Due to lower gearing the load with each downstroke is much less than when standing, but it happens repeatedly"

RESPONSE B: Well......no. I explained most of this above, but the majority of this has to do with something called the length-tension relationship of the muscle. The mucsle is in a better prestretch to contract at maximal force than it is when seated....it also requires a lot more stabilizing force to pedal standing - that's why it causes more fatigue.


"I consider myself a masher, not a spinner, so I have relatively low RPM's versus when I'm geared. On flat terrain though, I spin out just like everbody else. On a geared bike, if people mash while seated, I think this is when damage can happen. In my recollection I've hurt my knee when mashing a big gear seated, but never when standing."

RESPONSE: This is true, but due more to patellar tracking. If you are pushing a big gear when on the front of the saddle (as happens when climbing steep terrain) you effectively shorten your saddle height (by being forward on the saddle) and create excessive friction on the undersurface of the patella. This is probably what you are feeling when you stated the above.

I know people get all nasty when they post buisness info on this site, but I'd just thought I'd try to help out. I am a PT & do gait and cycling research for a living and if you ever need more info you can check our website at:
http://www.healthsystem.virginia.edu/internet/pmr/GaitLab.cfm
 

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Thanks for your input. It's nice to have discussion from someone who has on-the-job experience in this matter.

jayoutside said:
2) "When the knee is flexed, the joint "unlocks" and the tibia can rotate slightly upon the femur. When the leg is straight however, the joint "locks" and there is no rotational movement."

RESPONSE 2: big problem with this statement and I think you may have heard this the wrong way. Yes, it is true that when fully extended (0 degrees or into hyperextension) the knee goes into a "locking" position called the "scewhome mechainsm". Basically, what happens at this point is that the femur and tibia rotate on each other to increase the congruency of the joint surface and lock the knee. So yes, this happens, but its more like an on/off effect. As you approach this 0 degree locking point, the knee does not become more stable as stated. Its either locked or not locked. Its an anotomical thing. The knee is no more mechaincally stable at 3 degrees than it is at 40 degrees.
I'll have to go get on the bike and look at this again, but my knee is fully extended (and therefore locked) on the downstroke. Not all of the downstroke, because that would look dumb, but much more of the downstroke than when I'm seated.
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jayoutside said:
B) " When I sit and spin on a geared bike, the powerstroke happens when my knee is more flexed than when I stand, and is therefore less anatomically stable and more likely to stress the ligaments. Due to lower gearing the load with each downstroke is much less than when standing, but it happens repeatedly"

RESPONSE B: Well......no. I explained most of this above, but the majority of this has to do with something called the length-tension relationship of the muscle. The mucsle is in a better prestretch to contract at maximal force than it is when seated....it also requires a lot more stabilizing force to pedal standing - that's why it causes more fatigue.
Can you expound on "requires a lot more stabilizing force to pedal standing" please? Here's my logic and tell me if I've made an error: if the knee is "locked" it takes the burden off the muscles and ligaments to act as stabilizers. If the knee is locked on the downstroke, then it's more stable than when "unlocked." My knee is "locked" (at least for a little bit) on the downstroke when standing but not at all when seated. The knee is therefore more stable when standing (joint is extended) than when seated (joint is flexed).

Or did you mean stabilizing force for whole body posture since we're not sitting? I read your statement as "stabilizing force to control the knee joint specifically."
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jayoutside said:
"I consider myself a masher, not a spinner, so I have relatively low RPM's versus when I'm geared. On flat terrain though, I spin out just like everbody else. On a geared bike, if people mash while seated, I think this is when damage can happen. In my recollection I've hurt my knee when mashing a big gear seated, but never when standing."

RESPONSE: This is true, but due more to patellar tracking. If you are pushing a big gear when on the front of the saddle (as happens when climbing steep terrain) you effectively shorten your saddle height (by being forward on the saddle) and create excessive friction on the undersurface of the patella. This is probably what you are feeling when you stated the above.
Actually it's my lateral collateral ligament that got strained. The patellar cartilage is fine.
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Oh yeah Jay, would you (do you) do anything different for a singlespeed bike fitting than for a road bike fitting? What I mean is, since I mostly sit and spin on my road bike versus stand and mash a lot on my SS, I've found that I like two very different positions. I'm low and flat on my road bike but am high and upright on my SS.

As far as you know, has anyone done any research regarding bike fit specifically for a SS mtb? Most of the biomechanical research I've looked up was based on a road cycling model (but it's been a few years since I've tried to look up anything).
 

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I dont think that I've ever seen anyone lock a leg and pedal, even standing the leg is never comletely locked. When doing leg presses or extensions locking the leg/knee is very stressful.
 
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