I've been riding for about a year, and was riding quite a lot the earlier half of this year and never really encountered any knee pains. These days my riding has mainly only been a weekly group ride every Sunday morning. We'll do anything ranging from 45-70 miles depending on the route/climbing.

2 Sundays ago i started feeling some pain in my left knee about halfway through the ride, progressively getting worse till i got home. Not really sure what caused it, as i haven't made any changes to my bike lately. It's a sharp pain, kinda centered around the bottom-underside of my knee cap. The pain kinda stuck around for about another day or 2 (off the bike) and then i felt fine the rest of the week.

This past Sunday i started to get the same pain much earlier on in the ride, and even ended up having to cut my ride a little short because it started to become too much. I thought 1 week between rides would have been enough to settle my knee, but apparently not.

Any ideas what it could be and what's causing it? Should i stay off the bike for a few weeks and just let it heal completely and hope it doesn't come back? I'm still feeling it a bit today (again, off the bike.)

Have you had a professional fitting? Sounds like your saddle may be too low, or too far forward. Also, improper cleat alignment or foot position on your pedal can cause knee pain as well. I would VERY gradually raise and adjust your saddle with each ride to see if it helps.

hmm, that would be pretty strange if that were the case, as i've been riding w/ my current fit settings for well over 9 mos without any problems... I guess it's always a possibility though

Lower gear, higher cadence.

The interesting thing is it would hurt less when i was pushing pretty good. When just cruising it would hurt more. If i stood up it probably hurt the worst.

You can go quite some time with a fit that's slightly off before developing any issues.

Start with rest, ice, ibuprofen. Continue with a proper fit. If that doesn't do it, see an orthopedist, sooner rather than later.

If its not tendon pain rthe google chondromalacia and make sure its not that, if it is then its likely something to do with bike set up such as lateral / rotational cleat adjustment. Whatever it is dont ignor it.

Yeah, definitely take time off. You say the pain is behind your kneecap. Is it directly behind the kneecap? If so, then it could be chondromalacia (with damage that is not easily reversible). But I would make sure it's not a muscle or tendon issue first. I would agree with experimenting some more with raising seat height, even if you've already been fitted, just to see if the pain goes away.

Be careful with the ibuprofen though! Make sure that when you attempt riding your bike again that you haven't taken ibuprofen in the past day. Why? Because it can mask pain -- and pain is a sign that something is wrong. I "ibuprofen-masked" my running injury and continued running on it because without pain I didn't realize there was a problem.

lower and more forward saddle adjustment helped me, but it's highly personal. ymmv.

Ibuprofen -- and actually, any NSAID, like aspirin or naproxen sodium -- not only masks pain, it reduces inflammation. (NSAID = non-steroidal anti-inflammatory drug)

Acetaminophen (Tylenol), in contrast, is not an NSAID and will only reduce pain.

That is true, which is why it is useful -- but not before a ride. However, if the issue is cartilage, anti-inflammatories aren't going to help. (Again, I seriously doubt the OP has cartilage damage, but it's always good to play it safe and get it checked out by an OS if the pain does not improve).

i think i'll take 2 weeks off the bike, and then go easy on the first ride back on and see how that goes. If it still happens then i'll definitely have to do some real problem solving.

Don't make the mistake of assuming that this is a fluke thing simply because you've been riding for months without issue. I've been riding for almost 6 years now and over the last 2-3 years I've had to address some fit issues that showed up only in specific circumstances, and only after a few years of riding.

My biggest issue was that my left knee would develop a pretty nasty pain on really long rides that involved lots of climbing. Always maintaining nice high cadence, so it didn't seem to be simply an over-use or over-stress injury. Finally I came to realize that only on especially long climbing days I spent more time out of the saddle, preemptively even, from the start of the ride to mix things up. Riding out of the saddle results in each of my feet leaning inward a bit at the end of the power (down) stroke. By installing some cleat shims under just that foot, I slightly changed the cleat interface angle enough to keep my foot from collapsing in as much and within weeks ( continuing to ride) my knee pain had gone away. That was maybe 9 months ago, and I've been riding pain free ever since, even on long mountainous days. Just Sunday we rode about 94 miles with over 12k ft. of climbing, and didn't have a lick of pain from the knee.

If you're having sever knee pain, chances are VERY high that it's a fit problem, and I highly recommend finding a good fitter who knows how to properly address foot/pedal/knee issues and make some changes. Otherwise, you may end up drawing this pain out longer than you'd like.

Good luck, and report back what you find...it's always helpful (or just interesting) to hear peoples success experiences with pain resolution.

-Jeremy

https://www.cptips.com/knee.htm may have some helpful tips.

I was in a similar situation. I had just been dealing with some soreness in my right knee for a few months, despite riding with the same fit since spring of 2010. First I tried increasing the saddle height, which didn't seem to help, and then I decided to also move the saddle back some...not a whole lot...just a little. Well, after two rides my knee doesn't feel sore and I actually feel more comfortable on the bike overall (less weight on hands). It's really something how little tiny adjustments to your fit can make a huge difference.

I had a somewhat similar problem a long time ago. One winter I was playing basketball and smacked my knee into another player's knee - was a little sore but didn't think much of it. That spring, on my first ride, my knee starting having a sharp, piercing pain behind the kneecap after about 2 miles of easy spinning. Gave the knee a rest, tried again with the same results. Only bicycling caused the pain, I figured it must be related to the frequency of motion. Every spring I tried to get back on the bike, but had the same outcome. 8 years after the first occurrence I finally started being able to ride, not totally without pain at first, but 3 more years later I was fine. I didn't have the knee checked because it only happened while cycling, and didn't feel that it was important enough to go through any procedure to get it fixed, if it could even be repaired. Someone in the physical therapy field did suggest that perhaps the knee collision altered the kneecap "track" and caused inflammation until it worked itself out. Not sure about that, but the fact that the knee healed itself after a while tells me it wasn't a major structural issue. Like the OP, I had no changes in the bike that would point to fit issues. In fact, I was riding the bike for at least 5 years with absolutely no knee problems, and when the knee started feeling better, I had not changed anything

Go to an orthopedist. You won't know what is causing this without an MRI. I'm currently recovering from knee surgery for a torn meniscus. Sometimes it felt ok and at other times it really hurt. Surgery was a few weeks ago and I feel much better now. I'm just starting to ride again. I'm not pushing it but it feels good so far. Don't try to self diagnose it. The doc may tell you that you just need to rest it, you might need physical therapy or you might need surgery. Take care of yourself properly.