With duff knees cycling is good option for me and I found this video very helpful with my iPad balanced precariously over the handlebars (no expensive hi tech bike here…..just a 20 year old past sell by date bought for my son after injury). The video was easy to follow and Floyd made it easy to follow his pace. I must say that the first week or two I was horrified that what I thought was the workout was apparently the warm up 😳. We have progressed a little but with bone on bone and not much cardio done in past 20 years we are taking it slow!!