“When your legs get tired, run with your heart”

“When your legs are/get tired, run with your heart” is a popular saying that has been printed on many posters. “When your legs burn, run with your heart” was cited on Twitter in May 2009 and “When your legs are tired, run with your heart” was cited on Twitter in November 2009. The authorship of the saying is unknown.
 
 
Twitter
patti digh‏
@pattidigh  
RT @hiwendee Found a great set of motivational running quotes: http://tinyurl.com/bjfb57 I like: “When your legs burn, run with your heart”
9:29 AM - 14 May 09
 
Twitter
Arun Charles
‏@livetorque  
“When your legs are tired, run with your heart.” ~
Unknown #Quote
6:08 AM - 4 Nov 09
 
Twitter
Jonathon Prince ☰.0 ‏
@JonathonPrince  
When your legs are tired, Run with your Heart! http://bit.ly/bObpR0
7:41 AM - 18 May 10
 
The Muir Family
Saturday, August 14, 2010
When your legs are tired, run with your heart!
Yesterday I ran another 5K race!
 
Twitter
Real Runners
‏@RunningQuotes  
When your legs are tired, run with your heart.
10:35 PM - 19 Apr 13
 
Ready to Run: Experiencing Life One Mile at a Time
Thursday, June 27, 2013
When your legs are tired, run with your heart
“When your legs are tired, run with your heart.” - Anonymous
 
Blue Moon Personal Training
July 14, 2013
20 Motivational Fitness Quotes
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“When your legs are tired, run with your heart”.  Source Unknown