My legs are very low, I can do over 300 meters running at a time without rest and can do no more than 1,000 meters in total in a walk.
However I am still working and standing as I do not work, I wait. Bizare not? ... I can stand like that for hours at a stretch, even four hours if needed! ...
I see quite a lot of work sitting down, because for some very small piece, it is good to rotate with the room, rather than running the room on the desk because it is easier to hold with fingers.