Question on cardio

Ok so cardio is my poison of choice lol, wanting to lose weight in my face an chest (man boobs...) an I've been walking every night around 30-40 mins total. Anyways, I recently had knee surgery, so I am not suppose to run (bad for knees anyways) so I stick to walking an bike riding. What are some indoor cardio workouts I can do? Keep in mind my recent knee surgery :(

Replies