I've been fairly active for the last five or so years, lifting weights and walking more. While it has absolutely improved my overall posture, I still regularly catch myself slouching in front of the computer.
It's just so easy to let yourself go, especially when I'm deep in thought for prolonger periods of time. Paradoxically WFH has had a negative effect on this particular point, since I can go for hours on end without anyone distracting me (but it's been positive on the whole since I can easier program my workouts and meals).
- a short stretch,
- a short light weight lifting session,
- making a coffee,
- cleaning up a small part of the house,
- doing a small step of any other physical chore.
Those can take 10 seconds or 5-10 minutes, depending on the activity. Usually there will be 1-2 longer breaks of this kind, and the rest are the shorter ones.
I especially like how some house chores goes away thanks to this!
By spending enough time in the right position, you will instantly know when your posture is wrong.
I mean you’re not wrong, being stronger is certainly relevant to being able to hold posture.
But I got myself up to lifting quite large amounts of weight and it had literally no effect on posture at all, at some point or another you have to also change your habits.
For me, good posture starts with awareness. I have poor proprioception so unless I see myself hunched in a mirror I'm not aware I'm doing it. I am a very narrow-focused person though.
The other part of posture is just working at it long enough to build a connection to those important muscles. Teaching someone to have good posture is like teaching someone to wiggle their ears. Some people were born with that control and other people just don't even know what to do, mentally, to activate those signals.
Final part is to adjust what feels 'right' so that keeping your chest out more, your head back, spinal curves not too far in either direction, etc, all feels natural. I fight with the feeling that I look like a jerk when I'm just holding proper posture.
That all said, I think focusing squarely on your lats and lower traps can be a good starting point for folks looking to fix their posture. Yes, it's more than that, but it was one thing that helped, in addition to everything above, for me.
You need to consciously fix your posture. Talk to a specialist. They will show you how you are supposed to sit/stand, and it will take months of work to fix it and create the new habit of standing/sitting properly and not like a potato :P
Feel free to pick workouts that seem to disproportionately rewards your progress. Absolutely ignore that the game might say “very light workout: 50 calories burned”.
In a week or two, you will find yourself no longer having absolute zero core muscle && lower body mobility && sense of balance. Allowing yourself to easy workouts isn’t a self disservice either, it leads to training more diverse muscles, which would not occur by just looking up a single be-all workout solution to train specific muscles then failing to follow through.
Standalone USB controller charger and a cheap USB soundcard might be useful too in conjunction with above.
Stretch and open your chest. Loop a band around a rack and around your head and turn your head side to side against the band's resistance.
Rows. Flyes. Good mornings. Shrugs. Wide pull ups.
Practice moving with good posture. Do you lose it when you pick something up?
Roll your shoulders up, back, then down. Walk with your chest forward. It will feel exaggerated.
Being more aware helps you correct it. Mirrors are a great way to do that. Not honestly sure how your bicep comparison is relevant, but people look in front of mirrors to correct form for their bicep curls too.