Elaine Stritch in her 2 and 1/2 hour show starts with the phrase:
As the prostitute said "It's not the work, it's the stairs"
In an interview with Parkinson she mentioned an interest in finding
the origin of this quote.  I have done a number of searches using the
similiar parameters to those detailed below:
"work it's the stairs" Hooker OR Prostitute OR Whore OR girl OR lady
OR stripper OR exotic

Can anyone shed some more light on this?

Extra $5 tip available if in the next 24 hours

Couldn't find the origin of the quote, but I was humored by this
thread in which a few people were totally confused by the quote:
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&th=f9cb8d1565b36f9a&rnum=1

I found this quoted by Alfred Uhry (the playwright) in an Emory
graduation speech:
http://www.emory.edu/EMORY_REPORT/erarchive/2002/May/erMay.28/5_28_02voices.html

 & he added the words; "that gets you":  “It’s not the work that gets
you, it’s the stairs.”

  Here's the quote again used in reference to Maureen Dowd: 
"Advice to Maureen from ladies who stroll. It's not the work, it's the
stairs. "
http://www.lucianne.com/routine/archives/02-14-02.htm

All I could find.. will continue to look!

-Rebekah

Thank you both leep & starrebekah,

I enjoyed your thread leep, and I hadn't found that Grauation speech
starrebekah - though I had found the one in reference to Maureen Dowd.

Still, neither of these are the original...
Epideme

I can't find a reliable source for the quote, but I remember a joke
doing the rounds in the late 60's.

First hooker, "22 clients last night, I'm shattered, up and down
stairs all night"

Second hooker, "oh your poor feet"