Don't! lol!!!
My lower back/hip had been aching like crazy, and finally went to the chiropractor (sp?) yesterday. (we just got health insurance again! Yay!! :) )
He did 3 or 4 adjustments, as he said my pelvic was out a bit. ~ From always sitting with my right foot tucked under me! Apparently it messes with your pelvic/hip socket? I go back again Thursday morning.
He suggested I use a small box, etc as like a footstool, when on the computer or sewing. It is very hard for me to just sit flat on my butt!! And not tucking one's foot is a very hard habit to break I'm discovering! lol!!!
I posted on Facebook about this, and several said "I do that too!" So I thought I'd let you all know what I found out. :-)

I had always heard that posture was so important. I remember seeing older women sitting very straight with their backs not touching the chairback! One of our hand quilters died last year at age 98, and she still carried herself so tall and straight. She walked tall and did not use a cane or walker. She is an inspiration for me to sit straight, and don't slouch, as my mother used to tell me!

I keep a small chest under my computer desk to put my feet up on. But sitting on the couch, well my feet are always up or under me, lol Hard to break old habits!

I must sit on my foot! Two summers ago my knee and thigh were a bit sore--and when I tucked it under me at the computer something snapped. The doc said my tendon popped over my knee cap and to not tuck my feet under me any more. But, I still do. :roll:

I agree! I have a foot rest, but I sit with my leg crossed, one foot on the footrest. NOT good!

Also -- I was going thru physical therapy in 2001. My back was hurting and no meds were helping. DH (boyfriend at the time and hadn't been in my car much) and I drove to Reno and back. He said HIS back was hurting. We'd used my Caravan. I decided I'd trade it in and see what happens. NEVER had another lower back problem after I got rid of the Caravan!! Now, to really understand how something can botther your back, I was driving only 10 minutes to work and back every day and occasionally long distance.

I know, it's amazing isn't it? Little things you'd think wouldn't matter - apparently do! And as I pulled this up to read it, I realized I am sitting with foot tucked - again! :shock:
:D

I used to read with my foot tucked under me. One day my foot fell
asleep and I jumped up and heard a crunch. I broke my foot.
That was the last time I ever sat with my legs tucked under me.

Oh Pal!!! How terrible for you!!! I think that would have cured me of doing it too!

I love to sit with one or both feet tucked under me. (In fact, I just realized I am sitting on my left foot right now!!) I take yoga classes several times a week to keep my body "balanced" and work out the kinks. It really helps---I have been going for about 8 months and I am in much better shape than when I started.

I still sit that way on the couch but not sewing or at the computer anymore. I have alot of back pain as it is and that makes it worse. However for many many years I sit with my left foot under me and my mother used to tell me that it was going to injure my knee. Well guess what? Its my right knee I have alot of trouble with. :lol: I think sitting on my with my left knee bent for years kept it stretched and flexible and its fine. :wink: