Many athletes go to great lengths to get any edge they can against their competition; this often includes taking performance-enhacing drugs. “If you’re not cheating, you’re not trying (to win)” (“If you aint’ cheatin’, you ain’t tryin’”) is a popular sports saying.
 
NASCAR driver Richard Petty, in a 1972 newspaper article, was said to have once remarked, “If you ain’t trying to cheat a little, you ain’t likely to win much.” Also in 1972, a television character (a rodeo rider) had as his motto, “If you ain’t cheatin’, you ain’t trying’.” The saying became popular by the early 1990s.
     
 
Google Books
The Dictionary of Modern Proverbs
Edited by Charles Clay Doyle, Wolfgang Mieder and Fred R. Shapiro
New Haven, CT: Yale University Press
2012
Pg. 37:
If you are not cheating, you are not trying.
1982 Alastair Fowler, Kinds of Literature (Cambridge, MA: Harvard UP) 99: “Even our sayings are prefaced by opening formulas (‘Like they say, if you’re not cheating you’re not trying’; ‘As the saying goes…’)” (italics and ellipsis dots as shown).
1992 Boston Globe 27 Dec.: “First of all, rules are made to be broken, I don’t care what you’re getting involved with. If you’re breaking it [sic], you’re trying to win. If you’re not cheating, you’re not trying to win.”
The proverb is most often used in reference to athletic competition.
     
17 March 1972, Omaha (NE) World-Herald, “Actor Coburn Enjoys His Role in ‘Honkers’” by James Bresette, pg. 37, col. 2:
James Coburn stars as cowboy Lou Lathrop, a rodeo rider who’s grown old without growing up.
 
“If you ain’t cheatin’, you ain’t trying’” is his motto, and he lives up to it, cheating plenty and being plenty trying.
   
2 July 1972, Des Moines (IA) Sunday Register, pg. 4D, col. 7:
DRIVERS JUST TRYING TO FIND LOOPHOLES…
‘Cheatin’’ No Sin in Nascar Racing
By Shay Glick (Los Angeles Times)
RIVERSIDE, CALIF.—Richard Petty, king of Nascar drivers, once remarked: “If you ain’t trying to cheat a little, you ain’t likely to win much.”
 
6 November 1983, The Sunday Oregonian (Portland, OR), “Weekend warriors enjoy playing guerilla games” by John Snell, pg. 1, col. 3:
Their team was disqualified from two games for cheating. On one occasion they tried to tie their flag down to make it more difficult for the enemy to steal it.
 
Conway justified the tactic, declaring, “If you ain’t cheatin’, you ain’t tryin’.”
 
16 November 1993, St. Louis (MO) Post-Dispatch, “Canuck ‘investigates’ new refs” by Dave Luecking, pg. 1B:
“As my good friend Marty McSorley once said, ‘If you’re not cheating, you’re not trying hard enough to win.’”
 
21 November 1993, Chicago (IL) Sun-Times, “The Scoop,” pg. 24:
“All I know is if you’re not cheating, you ain’t trying. But I’ve never been caught doing anything as underhanded as that.”
 
26 July 1997, The State (Columbia, SC), “Panthers Notes,” pg. C6:
“I go by the motto, ‘If you’re not cheating you’re not trying,’” Kragen said.
 
28 September 1999, Rockford (IL) Register Star, pg. 5C, col. 1:
Former major-league pitcher Larry Sorensen, who admits now that he scuffed baseballs with hidden sandpaper late in his career, summed it up this way: “If you ain’t cheating, you ain’t trying.”
 
ESPN Magazine
KYLE TURLEY
NO. 115 (09/30/2002)
DP: Would you cheat to win?
KT: If you ain’t cheating, you ain’t trying.
 
Google Books
Freakonomics:
A Rogue Economist Explores the Hidden Side of Everything
By Steven D. Levitt and Stephen J. Dubner
New York, NY: HarperCollins Publishers Inc.
2005
Pg. ?:
An athlete who gets caught cheating is generally condemned, but most fans at least appreciate his motive; he wanted so badly to win that he bent the rules. (As the baseball player Mark Grace once said, “If you’re not cheating, you’re not trying.”)
 
13 February 2007, Daily Herald (Chicago, IL), “Want to stop cheating? Send a driver home” by Jenna Fryer (AP Auto Racing Writer), sec. 2, pg. 5, col. 4:
Still, cheating also is celebrated as a quaint piece of NASCAR culture. If you ain’t cheatin’, you ain’t tryin’, right?
 
The Street
Google vs. Apple: If You’re Not Cheating, You’re Not Trying
By Richard Saintvilus 07/10/12 - 10:47 AM EDT
NEW YORK (TheStreet)—There is a famous mantra in sports that I have always appreciated: “If you are not cheating, you are not trying.”