In reply to Chopper:
When I was recovering from my hip replacement the physio gave me exercises with a theraband around my ankles, to build abductors/adductors (still can't tell which is which...) plus walking backwards. Which I found I was rubbish at. Since then, and before the gyms all closed, I would add 400 metres or so of walking backwards on the treadmill at the end of my workout. Probably looked stupid, and not seen anyone else doing it, but I certainly got better at it - and no need to keep looking behind...