Knee Pain only from Outdoor Riding

Since I do not know what to do any further with doctors I would like to ask you so maybe I can get any good advice.

2020 I rode around 14000 km withouth any knee problems (even though I know from hiking that my left knee is a bit vulnerable). At the End of 2020 and the beginning of 2021 I did the SSBase I+II without any knee problems (I skipped the low cadance intervalls though).

In Febr. I did a 180 km race and from there on my odyssey started. I have had so much pain in my left knee that I was not able to walk properly steps down was the worst. I went to the doc and he said that I have a heavy inflamation in the knee something with the patella tendon. After a cortison injection (that did not help) he ordered a MRI Scan. The result was inconspicuous. He said I have a knee as a youngster (I am 44 years old).
I waited until I did not feel anything in the knee and waited some weeks more (it was mid mai already). From there on it is always the same. I start very slowly and after a few rides I get pain in my knee. I ride a gravel bike.
I did a 650 km ride with my E-Cargo bike and the family in Sweden last year without any problems.
So I came back and made an appointment for Bike Fitting (my bike was fitted the last time March 2020 but I wanted to be sure) The appointment was postponed due to corona and in Nov. I finally got fitted. He found some things (like cleat position and adjusted the sattle) and said that should fit the bill.

I put the bike on the indoortrainer to get back in form (I did 6 sessions) without any problems and went out and did a 40km ride 26 km/h avg so nothing heavy. Boom… knee pain. I waited now a couple of days and stated to go back on the indoor trainer and there I do not have any problems (today I did a 1h FTP Test without any problems).

There are some theories I have

  1. It could be the cold. But I ride in the cold with the cargo bike and have no problems and I did it 2020 as well without any problems.
  2. I am never in the drops when I ride indoor. Maybe it is a stretching problem?
  3. When I ride outdoor I have long cycling pants on. Maybe they fix the kneecap which causes problems. But I haven’t had any problems 2020 and I wrote a lot in long pants.

I do not know… these are just guesses.

To specify the pain. It is not outside but inside of the leg. If you touch the kneecap it is in the little hollow directly beside it.

Maybe one of you has a tip for me I am so annoyed not being able to cycle properly. Since I do not have a driver licence I do really everything with the bike and this handicapes me a lot…

Have a nice day and thanks for reading!

More guesses from me and sorry it not a solution,
I hope you find one soon. Indoors you perhaps ride at a more constant, comfortable cadence and force (left v right) is balanced, whereas out side its more varied and you naturally at points to balance, etc put more force through one leg.

Jon made a great post on knee injury - identifying and addressing, here:


Many thanks for your answers! I have had a look into Jons Thread and there are many approaches that I can try. I will go forward with this and (fingers crossed) hope it will help.
I have read about pedaling techniques in his thread and remembered that I changed my one from mashing to spinning last winter. That might be one of the things that I will try.
Best and take care!