The most common and most likely answer to this crossword clue is the 6 letter word KILTER
K
I
L
T
E
R
Buddy explains!
The straight part
We know that "in poor shape when out of this" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in poor shape when out of this = kilter.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does KILTER mean?
KILTER noun- (usually in the negative) (Good) condition, form, or order; fettle.
- A hand of playing cards which is useless; a dead man's hand.