2:59 !!!

Sounds like your right unless it's a torn meniscus, which I doubt. More than likely "Runners Knee". Again it's a pretty common pain that can be remedied with some rest, icing and short term use of ibuprofen and some core strength training focusing on your knees. It's also a good idea to check your shoes making sure there not worn-out and the correct shoes for your feet! Sometimes "Runners Knee" can be brought on by running too many miles too quickly.One must remember that subtle increases/buildup in mileage and speed are integral to any any training program!

Thank you Tom! I believe that my training is carefully planned. So beside the things you mentioned I am curious if there is anything I could do better in my training.

I would concur all said. Building up training is a challenge and everyone reacts differently to the balance of distance and tempo. Some people have distance limits that their body reacts to harshly. Run for a few weeks below your limit and try increasing speed work. Then increase the disntance for a week and easy pace and see how you feel. Ice and rest is the best medicine for runners knee. Been there sorry for the issue.

Martin. I find that when I get my mileage high, I have to do most all my running at a very slow pace for a long time before I can introduce another speed. You have to have that cardio base built. That or do the faster training and keep the mileage down. I ran my second sub 3 marathon on 3 days of fast running a week with 3 days of cross training.

Hi Martin. If it is runners knee, this is caused when there is an imbalance of strength between the vastus lateralis and the vastus medialis. I had a bad case of runners knee several years ago and went to physical therapy for it. It means the vastus medialis is too weak and the vastus lateralis is stronger and pulling the knee to the right. My physical therapist had me do a lot of leg extensions with my toes pointed more inward and he would have me hold it fully extended for five seconds each time. It was brutal. He also had me riding a bike. Which REALLY works that vastus medialis. All of that worked like a charm. It did take a couple of months or maybe a little longer to fully recover from that, but sticking to those exercises worked great. Hopefully that's all it is and not something more serious. Good luck!

Addie :)

Hey, thank you all! I definitly have imbalances, but I never did more stretching (daily 5-15 min.) and strength training (~2 × 15 min. weekly). Thought I would be on a good way. I will try a little jog today and see how the knee responds. Funny: yesterday I iced the wrong knee! (-: think that's a good sign...again I see that I want too much too soon. I am again reading Joe Henderson's "Long slow distance" and I believe I should take it even easier than before and just try to enjoy running as an important part of my life.

Again, thank you very much for your advice!