"I've been hiding from exercise. I'm in…

“I’ve been hiding from exercise. I’m in the fitness protection program” ‘’ a pun on “witness protection program”—is a jocular saying that has been printed on many images. “Fitness protection program” was cited in a 2007 book.

“No, I don’t exercise. I’m in the Fitness Protection Program” was posted on Twitter on November 22, 2009. “I’ve been hiding from exercise too long. Time to come out of the fitness protection program” was posted on Twitter on December 6, 2010.

Google Books
I’m Your Man
By Susan Crosby
Don Mills, ON: Harlequin
2007
Pg. 127:
“Can’t exercise at all. Not allowed.”
(...)
“I’m in the Fitness Protection Program.”

Twitter
Beth Drennan Jokes‏
@BethDrennanJoke
I’m entering the Fitness Protection Program.
4:42 PM - 14 May 2009

Twitter
Notorious d.e.b.‏
@debihope
No, I don’t exercise. I’m in the Fitness Protection Program.
9:54 AM - 22 Nov 2009

Twitter
Jeremy Johnson‏
@123JeremyJ
I’ve been hiding from exercise too long. Time to come out of the fitness protection program.
11:19 PM - 6 Dec 2010

21 December 2013, The Ledger (Lakeland, FL), “A Guide to Last-Minute, Polk-Based Gifts” by Matt Reinstetle and Gary White:
Locally made products are the rule at Two Hens & a Hound on SoKen. The shop, which shares space with Fast Frame (117 S. Kentucky Ave., Lakeland), carries T-shirts from Co-edikit, a Lakeland company. The shirts ($18.50) bear such messages as “What doesn’t kill me ... had better start running” and “I’m not allowed to exercise ... I’m in the Fitness Protection Program.”

Redland (CA) Daily Facts
Riding Redlands bike lanes is non-cyclists’ adventure
By Toni Momberger, Redlands Daily Facts
POSTED: 02/07/15, 4:57 PM PST
(...)
My tired joke that I don’t exercise because I’m in the fitness protection program wasn’t funny so much as pathetic just then.

Google Books
Wicked Heart
By Leisa Rayven
New York, NY: St. Martin’s Press
2016
Pg. 150:
I whisper, “Not a lot of people know this, but I’m in the fitness protection program.”

He tries not to smile. “Is that right?”

“Yep. Every new year I’m hunted by gym memberships, but they haven’t found me yet.”