Anyways all jokes aside if you want to wipe your memory of big kite industry propaganda for a minute guys then just look at cliff diving..... a big flat surface aka belly flop creates the most pain but a streamlined small surface creates far less
Now imagine you were to drop each board straight down
Which one would be better for ya knees?
So that's thr up and down axis taken care of
Now for the next part that whole left to right business
What handles chop better a sup or a kayak with its rocker ?
Or how about just any craft with more rocker and one without?
Anyways my analogy socks but hopefully yas get a bit of an idea on what I'm trying to put forward.
There's a reason why marathon distance running shoes like hokas with inches and inches of foam are being used over the more classic style new balances (who have now got the mega thick foam version too) because the impacts can indeed hurt your joints etc
But it's very very clear to me *again I use both styles of boards regularly* that the impacts from my wakestyle boards with loads of rocker and boots is far less and therefore better for me then a surfboard.
So give your knee surgeon the flick and grab yourself a wakestyle board and some cushioned boots
As a side note 15 minutes of training actually increases your tendon and joint strength longer then 15 can start to make it plateau and about a hour or 2 can start to degrade it, so don't run for more then 15 or 30 minutes and then lift heavy (but not too heavy) for bone density and you'll be surprised how robust you can make your once torn up withered old joints.
I'll try find my favourite knee rejuvenation podcast from gavins training day
www.cloudbasemayhem.com/?powerpress_pinw=1046-podcast so essentially ex pro skier blew knees up skiing they were useless for 20 years but with some proper training led him to be able to do 100km walks and runs each day after day
There's no reason why you guys can't do it to and then you can finally retire this old false adage that once you get old and Decrepit you gotta hang up the twinny for a surfboard. It's simply not the case or true in anyway shape or form.