ok.

i understand that certain movements can cause back pain
in people whose backs are not adequately stretched, conditioned, etc.

what i want to know is,
in a person whose back IS in perfectly stretched and strong condition,
will these same movements
a. set the stage for later problems,
b. tend to prevent future problems, or
c. have no effect.

i am referring to motions that people with back pain should not do,
such as
bending from the waist to pick up things from the floor,
getting out of bed bent from the waist,
sitting for a long time

that sort of thing.

do they actually cause problems for people who have no back problems?

what about someone who may have had a history of back pain,
but who is currently stretching and strengthening, and having no
recent problems?

?,
wle.