ELI5: If slouching is so bad for our back, then why is it so much easier and more comfortable?

I think it's fair to note that the way you sit has a lot to do with it. I have lower back issues from horseback riding all the time, so sitting with my knees at a 90 degree angle to my spine just fucks everything up in my joints. I always scooch to the edge of a chair so my knees are lower than my pelvis. That makes all the difference. If I sit with my knees up, I almost always slouch to compensate for the reduced mobility in my spine from my back injuries. If I sit with my legs at 90 degrees, I can't ever get comfortable, and sitting straight AS WELL AS slouching is painful. So you need to find a comfortable sitting position (I've read some ergonomic advice saying knees slightly elevated above pelvis is best. Others say 90 degrees. I dont like either. Find what works for you).

And don't strain your muscles for it. You just need a slight tension in your lower abdomen to support your lower back and a gentle pressure in upper back to support the shoulders. If you're not relaxed while sitting straight, you're going to tire out much quicker. Core exercises help develop the appropriate muscles, as well. (This coming from someone who needed PT to re-develop the appropriate core to compensate for my injuries, so take it with a grain of salt)

/r/explainlikeimfive Thread Parent