Cardio: Stair stepper vs bike

[Vennom96]

Cardio question:
I don't run on the treadmill b/c it hurts my knees and feet so I usually do the stairstepper or bike for 20 min. Is doing the bike just as effective for fat burning as doing the stairmaster for 20 min?

 

[hornedfrogs07]

Probably not quite as effective, in terms of total calories burned, but the difference would be miniscule, and the important thing is that you do SOME form of cardio.