Is there a reason why sitting with your back straight is the "rule" at meditation?

[Clarky000]

I've watched several Leo videos about how to mediated, and in most of them he says that you should sit with your back straight, with no support on it. Why is this the case? Couldn't I meditate just lying on somewhere comfortable?

Sorry if Leo changed his opinion on recent videos about meditation, I haven't watched them.

By the way, I've been meditating for 3 months straight, at least 20 minutes a day, with no miss at all, so back pain is not an annoyance anymore.

[ajasatya]

@Clarky000 It's just experience. You can try any other posture to see what works best for you.

If your body is all loose, you might become sleepy. If you're standing, you will probably feel too stiff.

[nistake]

Mainly because of alertness. Posture doesn't really matter, but it's recommended to sit with your back straight because you can remain alert that way and alertness is really important during meditation.

If you can remain alert 100% while lying down, then it's not necessary.

[Rilles]

During The Guided Meditation Leo says "sit as if youre watching your favourite TV show" so it doesnt really matter, dont get too hung up on the details. Find what works for you. 

[Arcangelo]

Kundalini

[Spaceofawareness]

I find if I’m slouching my breathing comes more from my chest as my stomach muscles tighten. But then, if you have back problems like I do, you will likely want to find some way to sit which doesn’t aggravate this discomfort, so do what works.

[astrokeen]

In Yoga a straight back is essential for meditation. It supports the opening of channels for the kundalini to rise. Similarly, for pranayama (yogic breathing exercises) correct posture is considered to be vitally important. 

[Javfly33]

6 hours ago, Meta-Man said:

I just sit like a sack of potatoes in my armchair. Works just fine. And it’s authentic

Thats why you are still not gone by now, man.. gotta sit with your sit straight.?

@Clarky000 Because if not you will probably fall asleep.

[Osaid]

It keeps you alert and helps you breathe properly. I tried meditating without any attention to posture and it was definitely harder.