"I feel like I was an outcast, I was left out because so many people made fun of me. But when they saw me play sports, there was just something about me where people came to me and just stopped talking about me and started being more of my friend," Charles said in an interview with The Associated Press in which he opened up about the role Special Olympics played in his life.
Once he gained confidence by competing in the Special Olympics, the teasing stopped. The tutoring began. And Charles set out to prove wrong the doubters who said he wasn't smart enough to get into college and would never play professional football.
"I had to fight all my life to prove to people that I can do those things," said Charles, who will pay tribute to the Special Olympics this weekend as one of 1,000 players who will lace up customized cleats reflecting their charitable endeavors as part of the league's "My Cause My Cleats" campaign.
That's double the amount of players who participated in the inaugural effort last year.
Special Olympics "was the drive that sparked me, that led me to do all those things, and look where I'm at now," said Charles, who joined the Denver Broncos this season after nine years in Kansas City where he's the Chiefs' all-time leading rusher and boasts the highest career rushing average (5.5 yards) in NFL history.
Charles' reddish-orange cleats honor the Special Olympics that changed his life when he was 10 years old and won a gold medal in track and field. More importantly, he came away with a newfound confidence and, eventually, acceptance.
"People that have a chance to compete in the Special Olympics, they build up confidence - confidence that we don't have in the classroom, confidence we don't have around 'normal' people," Charles said. "You believe in yourself."
Charles began to share his story two years ago when he gave a speech at the opening ceremony of the Special Olympics in Los Angeles in front of more than 60,000 people.
"A lot of people where happy that I did it. They were surprised. They didn't know my history or my story about the Special Olympics," Charles said. "I competed in the Special Olympics when I was young in middle school and that's when (I realized) that I can do something in life."
Other players supporting the Special Olympics with their calico cleats this weekend include Aaron Rodgers, Tyreek Hill, Joe Flacco and Kareem Hunt.
Many players worked with Nike, Under Armour and Adidas to design the cleats they'll wear in games this weekend. Others used their own designers.
Von Miller is wearing two different cleats: one has eyeballs and eye charts on it to promote his foundation "Von's Vision," which provides eyewear to underprivileged kids, and the other is a black and purple cleat with detachable butterfly wings on the back in honor of a childhood friend who was diagnosed with lupus.
Domata Peko's specialized shoes support the "Save the Children" organization and also features a Syrian flag.
"The reason I put Syria on here is because my wife is from Syria and they are going through a really tough time right now," Peko said. "Save the Children has been doing a good job with the refugees that are over there. I just wanted to show some love to the children."
Derek Carr is using his cleats to talk about his son, Dallas, who was born with an intestinal abnormality, and other players, including Malcom Jenkins and Mike Evans will use their cleats to showcase social justice issues
Broncos running backs coach Eric Studesville will wear specialized sneakers honoring the Donate Life kidney donation program in honor of his late mother who donated a kidney to a family friend several years before she died in a motorcycle accident.
Players are increasingly wearing custom-designed cleats before games to make a statement, fashion or otherwise. The king of the customized shoes is Steelers receiver Antonio Brown. But players can only wear them during warm-ups because NFL rules prohibit players from wearing shoes during games that are not black or white with a team color.
Week 13 is the only weekend that players don't have to worry about the league's fashion police flagging them for fines over their footwear.
Afterward, the stylish shoes will be auctioned to raise money for the charities.
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