I'm no expert on this. My bf (who rides road) had ongoing patellar tendonitis in one knee for a long time and finally had it investigated a few years ago. Seems the groove his kneecap rides in is a little shallow. A tight IT band pulled on the patella, causing tendonitis. He did some massages to keep the patellar tendon loose and some temporary taping of the kneecap to keep it on place. He also started with the foam roller to loosen the ITB. It's been a couple of years and he has been free of knee pain, he still uses the roller regularly and does a few basic stretches every day. He uses Speedplay and Frog pedals for the float.