On the fast track to decline

16 months ago I was a 53 year old superman, cycling 200 miles a week, sailing, gardening, etc etc… All of that is gone now. I don’t see I will ever cycle again. I have put on 2 stone, my heart rate is up 40%, I sleep 3 or 4 hours a night, watch TV all day. This summer I will be a house prisoner and next year I might lose the house.