Apple watch always thinks I'm standing

Ah! I've checked the Apple documentation... and the watch is working as expected.

From page Use Activity on Apple Watch - Apple Support:

"The Stand ring. This represents the number of hours in which you've stood for at least 1 minute. You'll complete the Stand ring if you stand up and move a bit for at least 1 minute during 12 different hours in a day. "

So, we're just hitting our Stand Goals, as this is tracking each hour to ensure you've stood for at least 1 minute in that hour. If you have, the hour counter will index by 1.

I also have this issue. I received my 42mm Apple Watch Sport on Tuesday this week, and each day it records that I am standing for the entire time that I'm wearing it. Yesterday it stated I was standing for 16 hours... I was only awake for that long! Thinking of calling Apple Support to enquire further as there is something clearly not right.

A stand hour is where you are stood or moving around a little. So if I'm moving around in bed during the night - my wife complains about this - then it will record that movement as standing

Same