Without spending a lot of money, and now confined to home , because of current pandemic, and at age 89, I have purchased a 2nd hand stationary bike, and I have a couple of dumbels, I can really get my cardio working. The secret is to start slowly, ride every 2nd day, and slowly increase your time, until you are puffing. Riding the bike places nil stress on, feet,knees, ankles,hips or back. Check with your doctor for his approval. THE dumbels are great for both sexes, and for woman helps guard against osteoporosis in the shoulders. I paid only $50 (Australian ) for the bike and it is almost brand new. Dumbels, of course vary in weight, but 2nd hand, are as cheap as chips. Don't let your condition get you down, remember , the reward will get you smiling, as you acheive. Best wishes from Australia.