... sometimes, you just really need to give your joints a break....
they really get hammered... or maybe you have Meniscus knee problems or something degenerative??
when I was in high school... I did a lot of sports... and track and cross-country... and my knees got like that. It was getting... way over-used and hammered and no real recovery time in between.
I had to just stop.
Or my knees would have gotten really messed up.
Sometimes, you just have to listen to your body....
My Hubby.. used to do competitive cycling... and he got that in his knees too. Like you, tests showed up nothing... but he had to stop competing.. his knees..... and the pain was just too much. Now years later... his knees are not well and he's had to have surgery. He even had surgery on it way back then, when competing.
What does the physical therapist say??? If they have no idea why your knees are like that... then why do things/therapy to it????
I would see... other treatments as well.... like Acupuncture too.
BUT if your knee problem is degenerative... or has to do with bone grinding on bone.. or the protective 'gel' in between the knee joints lessening... physical therapy is not going to necessarily bring back... knee mobility per say... because the problem is not muscular in origin....
all the best,
Susan