We are all working from home currently in the lockdown and here is what I have found and attempted to fix:
1/ my monitor was way too low. The proper ergonomic height is just below the top of the screen. This is so that your armpits are able to face forward. Any lower and you will need to slouch.
2/ standing for long periods of time is hard. I bought a gel pad for underneath and regularly have a stool nearby so I can adjust my standing. After 30 days I was alot more used to standing.
3/ get a keyboard. I was using my laptop keyboard connected to an external monitor before and that was quite comfortable. What you do not realise is that the height of the laptop affects where you please your wrists and arm. It is not in the most ergonomic position.
After adjusting for the above issues, I found
1/ My posture is alot better, shoulders are less internal rotated.
2/ My head is moving back and no longer at risk of developing a hunch back
3/ I need to embrace my core a whole lot more and be consious of doing it at the beginning
5 Percent a day 