@Vansan ....i know feeling of thinking you font need it. I did really well managing bone on bone for a few years and after swimming i felt amazing walking out of the pool.......until 3mins later it was all back again.
I'm at the beach and had a swim in waves-well a paddle to my knees thighs and could feel the current so limited my time....then a walk in soft sand for a bit an have clambered over fences and up and down -slowly carefully banks. Happy to report no ill effects the next day. Having a slower day today but will do a little swim again tomorrow
Just a different form of functional exercise