tension instead of compression on human spine?

[tiny-tim]

in most mammals, the spine is usually horizontal

in monkeys swinging from branch to branch, the spine has evolved to operate vertically under tension

in humans (and other animals that walk on two legs), the spine is in compression when vertical

did humans evolve from swinging monkeys?

would it be better for our spines if we spent some time swinging around, with our spines in tension?

or if we slept in a hanging position (possibly upside-down)? or on a horizontal rotating bed (with the ears at the centre)?

what would be the effects be?

[Proton Soup]

from the little i remember of Statics, it's not a simple issue of either compression or tension. let's say your spine is perfectly vertical (can't be actually because it is curved). well, once you begin to lean forward a bit, the anterior of the spine experiences compression, while the posterior starts to go into tension.

you have really evolved to experience compression and tension in all directions. some more than others, since you can train quite a bit of posterior tension with enough lifting.