Ideas for exercising my cat that had a stroke

My 5yo cat, Myrtle, had a stroke a couple months ago. She eats, drinks, & potties fine, but she's wobbly and can't get up on things (except the bed). She rarely runs because she falls over. She was a chunk before the stroke, but still active and played. Now she's getting very fat and rarely gets off the bed. Any ideas for how I can get her to exercise? I put her outside in a pen, always supervised, but she just lays there looking around (as you can see in the pic).

There was an episode of My Cat From Hell where a couple had a cat named Foley who had a stroke. Looks like this couple went on to set up a Facebook Cat Stroke Support Group: https://m.facebook.com/foleysjourney/