Now, young boxers like Nelson De La Cruz Jr. are making a name for themselves with the help of Acosta.
"Sports play a big part of children's lives," Acosta said. "They need something to do, especially when you are coming up in an area that's high in poverty."
That inspired Darren Swift, the father of Swift Fit., to open another door at the family's gym
"God put it on my heart," Darren Swift said, "because we have a large boxing community in the city of Philadelphia, but they don't have a lot of places to go."
Nelson De La Cruz Sr. rarely misses a practice.
"This is kind of a sport where it's like, you have to love it," he said. "You have to take it really serious, or you can get hurt in it."
"Sometimes when I do get nervous, I do underperform a little bit," De La Cruz Jr. said, "but every time I try to give my 110% as soon as I walk into the gym."
De La Cruz Jr. also gets to watch and learn from teen title boxers and junior Olympians like Team USA boxer Jason Moreno.
"He now has three national titles," former boxer Johnny Rivera said. "He won a silver at the U.S. nationals so that qualifies him for the Olympic trials this December."
And Juan Rivera, AKA "Little Johnny" or "Different Breed."
"He's definitely a different breed in this sport," Johnny Rivera said, "and with his faith in Jesus Christ."
"He's a 19 gold national champion and a two-time international gold medalist. He's won gold in Romania and two months ago, he won gold in Germany for Team USA."
Rivera's biggest fan is his dad.
"The sweet science to be able to hit somebody and not get hit and still hit them again," Johnny Rivera said. "There's something in that."
From De La Cruz Sr.to Rivera's dad and even Darren Swift, Acosta said he hopes these special connections go beyond Swift gym and into the community.
"wanted to learn how to box because someone stole his bike," Acosta said, "and the gym was above a police station, so he went in there, and look at what he turned out to be."
If you want to see the young boxers in the ring, you can check them out at Swift Fit's first-ever boxing tournament on Saturday, where you never know who might be in attendance.
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