Just watched the above You Tube post and thought it might be worth mentioning that she posits that those with kephosis might be better off Nordic Walking with a small back pack - have a look for her explanation. I don’t use either at the moment.
I am just getting into Nordic Walking and am enjoying it - can certainly feel when I am getting it right (technique slips now and again 😊). I started with a taster session, followed by a tuition session and am now just going out by myself . I may join in on one of the many group sessions going on at some point but I generally prefer being out on my own