I would love to be able to walk and hike again. But I have a lot of foot problems now, and have been trying to get them addressed medically. For awhile now I have even been driving the car from house to house, about the length of a football field, as to avoid the heat and foot pain. After being prescribed some pain medicine, and using it twice a day faithfully, I am improving somewhat. Enough that walk between the houses. It happens 4 times a day. So that is my cardio for starters. But I am aware I may have to move to a bike or something.