Originally Posted by
Snuffleupagus
The rule of thumb a lot of physical therapists will use is "let your pain be your guide" - I'd look at getting on the trainer first to assess how you're doing. Then, if it feels good, keep going. If it hurts, stop.
+1, I've got some knee problems from genetics and injury. If I find any certain effort causes knee pain, I stop it IMMEDIATELY. This is not the kind of pain you want to push through; that's not how it gets better.