“Your feet are hurting because u r kicking so much ass” is a running saying that has been printed on signs. “‘Your feet are hurting because you’re kicking so much ass” was on a sign displayed at a marathon in November 2006. “YOUR FEET ARE HURTING BECASUE U R KICKING SO MUCH ASS” was cited in January 2008.
 
       
The Global Reconnaissance Organization
05 November 2006
trample the weak. hurdle the dead.  
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[2.6mb avi video] i’d just seen someone holding a sign which said ‘your feet are hurting because you’re kicking so much ass.’ another noteworthy sign read ‘trample the weak. hurdle the dead.’
   
Elite Feet
Take a Dump In Your Pants If You Need To
Written by: Shane January 27th, 2008
(The following ins on a sign—ed.)
YOUR FEET ARE HURTING BECASUE U R KICKING SO MUCH ASS

CoolRunning Forums (Australia) 
rodthehornet
Posted 20 March 2009 - 08:45 AM
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The entire event was really cool - all the “bazillion” people cheering the runners on were amazing.  There were signs that said “Run like you stole something,” “A marathon is like a 10K with a 20 mile warm up,” “I just saw Mathew McConaughey - go catch him!” and “Your feet are hurting because you are kicking so much butt!”  There were more signs, but those were my favorites!
 
Twitter
Active.com
‏@active  
Classic Marathon Sign #732: “Your Feet Are Hurting Because U R Kicking So Much A**” Find your next 26.2: http://bitly.com/SearchMarathons
9:29 AM - 9 Jun 09
 
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Jonathan Gheller‏
@jgheller  
your feet are hurting because you are kicking so much ass:  http://flic.kr/p/9y7H2B
12:45 PM - 16 Apr 11
   
The Norwich Guidon (Norwich University, Northfield, VT)
Run, Marine, run!
Students compete in the ‘People’s Marathon’ for the USMC
By Ben Cottrell
Published: Saturday, November 19, 2011
Updated: Saturday, November 19, 2011 22:11
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One sign, held by a young woman, read: “I hear you runners have stamina, when this is over, give me a call!”  Other signs read: “Run like you stole something,” “Chuck Norris never ran a marathon,” and “Your feet are hurting because you’re kicking so much butt!”
 
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POPSUGAR Fitness
‏@POPSUGARFitness  
Your feet are hurting because they’re kicking so much a** & more fitness quotes http://fitsu.gr/21383537
10:55 AM - 18 Jan 12