No, not really. There are several floor exercises you can do with no equipment at all. You can also use household furniture such as a chair to help you. Try doing push ups with your feet up on a...
Press ups and sit ups
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Push Ups with varied hand positions.
Keeping your hands wide will work your Pectorals (Chest).
Keeping the hands close and the elbows...
A recumbent stationary bicycle is excellent equipment that won't be hard on your joints as it offers excercise while letting you rest comfortably in between.