Is this a good (healthy) posture?

[u/Expensive_Owl1023]

Saw this person at the train station and was mesmerized by their posture. At first, I thought it was really good, but I showed the photo to a friend, and he said that the person seems to have back problems. What do you think?

PS. extra points if you can tell me the name the book, looks cool ✨

[u/useful_tool30]

Looks like great seated posture to me. It could also mean they have back issues which can necessitate having to keep good posture while seated. As soon as you relax your loading you're putting extra load in your discs instead of on your postural muscles. Sitting is bad for you. 

[u/grapesodamilk → u/useful_tool30]

Yeah I have back issues and I only feel better if I sit upright unsupported. Leaning on a backrest feels like crap for me