Posture re-training: How long will it take for for my new posture to feel natural?

I've been working on improving my posture for health reasons.
I think I'm doing it correctly but it is causing moderate back strain.
I'm also finding it difficult to remember to always stand/sit 'tall'

How long does it take for the muscles to stengthen and also for the posture 'habit' to embed (roughly - I know it will vary)?
Answer:
I ve had a similar issue. i have scoliosis and use orthopedic inserts in my shoes to help correct posture. it did hurt, alot, i felt that i was walking wrong and that maybe they were done incorrectly. but after about 3 months i could walk in them without back strain or pain. It turns out that it takes a lot more energy to walk incorrectly then correct. i came out much straighter and with alot more energy and strength

Keep in mind my doctor told me to only walk in them sporadically for the first 2 months to get used to the pain of my spine realigning. but I'm a moron and just walked in them all the time. and it hurt alot for about 3 months. so who knows how long its would take to acclimate to a straighter posture at the recommended rate. maybe 5 - 6 months?

hope this helps

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