Wait until you get older & you won’t be asking this question! For myself i always stood, as i found it easier to feed from a bait apron, & to mend the line for the stick float. I now nearly always sit as with modern boxes & bait waiters i find it easier to fish for long periods without having rest my back. If you can catch sitting down then do so, because no matter where you stand there will always be a stone or a root just under your foot & you can never get level! Also the old feet get cold after prolonged periods. I know skeetex are totally insulated, but a 1 mile walk in them things & you need to sit down for the rest of the day.
To sum up, don’t be a hero & if you can sit down do so! There’s nothing to stop you standing up for some of the match.
Regards (last of the summer wine) Peter.

My brother and I were having this very conversation travelling back from the Trent yesterday.
He always stands, usually with a platform set up with his bait and stuff on. This is my 3rd season back fishing rivers full time – I stood for the first 2 but bought a an XL Penrose for this season. I think the main advantage is you can set up your stall the same way each session which means you can concentrate on the fishing rather than spending time and energy working around awkward rocks,roots, banks etc