Originally Posted by
cubewheels
You might have pre-existing issues if you need to extend your legs more frequently.
Although over-extension might feel okay or easy with the muscles, they're pretty harsh on the joints. Pro cyclists seem to avoid it as much as possible and compensating with the ankles (pointing them more than bending).
I also experience if I over-do it in the trainer in the form of pain behind the knees. It gets worse with higher effort such as when climbing. For me the pain goes away quickly and I'm okay the next day. I'm also making adjustments to my training to avoid over-extension as I only encounter it when pedaling out of the saddle.
OOS, pedal like Pantani:
Notice how he pulls his relaxed foot over the top with his knee, how is butt hardly goes up and down at all, how his knee bend at the bottom of the stroke is exactly what it would be were he in the saddle, and that he always rides OOS in the drops. I can't ride OOS at anything like his cadence, but I try to model my motions after his. When I do it right, it feels great. I think it is easier to ride OOS from the drops,