Most people perceive professional athletes as strong, aggressive and driven. As a National Football League linebacker, Keith Mitchell possessed all three of those qualities— but in 2003, a paralyzing injury during a routine play shook up his reality.

“I played the most alpha male position on the football field … and was one of the best in the world to do it,” Mitchell, who played for the Jacksonville Jaguars, told FoxNews.com. “My thing when I played was contact— I wanted to hit as hard and relentless all day long.”

Mitchell, originally from Texas, took the hardest hit of his career in a game against the Buffalo Bills on Sept. 14, 2003, and was forced into early retirement at age 31. He’d began his career at Texas A&M, and played for New Orleans Saints and the Houston Texans before ending up in Jacksonville for only two games.

Now 40, Mitchell lives in Los Angeles and has transitioned his life from one on the field to one on the yoga mat.

“The nature of an athlete is to sacrifice oneself for the sake of something outside of self … then judge when it’s not up to par,” he said. “For me, I had to go through a whole revelation of forgiving myself and my body and trusting myself.”

“If you look at most football players, age 40, they don’t have the vitality I have,” Mitchell added.

It all began when Mitchell was recovering from his devastating injury, and a nurse practitioner suggested using conscious breathing as a therapeutic tool to improve circulation in the body and aid healing. Mitchell was hesitant at first, but his vulnerable state left him open to new information. He found that breathing helped ease his anxiety, depression, anger and fear.

“It allowed me to not only deal with my physical body … but my emotional, psychological body. I was like, ‘What the heck is that all about?’ That’s when [I] began to see that body,” he said.

Mitchell avoided taking medications while he was recovering to detoxify his body.

“I made it a point because I had an intuition if I went down that road of drugs or certain medications, I knew I wouldn’t come back from it … I guess I was always wanting to be in control of my senses, my elements of myself,” he said.

He also began practicing yoga and, after his move to Los Angeles, decided to teach. He started a nonprofit called Light It Up, which provides services to at-risk youth, adults, veterans, and families in need.

“I’m looking for that person, the people who have never tried [yoga],” he said.

Mitchell has worked with congressman Tim Ryan (D-Ohio) to lead guided meditation on Capitol Hill and is planning to launch a nationwide yoga and meditation tour for veterans in the spring. He’s worked with schools across the country and sees the profound effect of teaching yoga and meditation firsthand.

“What I see when they give it a try is a whole different world that opens up [to] them,” said Mitchell, who added that meditation creates a self-knowledge for kids.

In working with veterans, Mitchell sees the need to diffuse the masculine, disciplinarian energy that has been conditioned into the troops of both genders and suppresses compassion.

“Like water boiling, [we’re] going to drop an ice cube in the whole thing and diffuse it a little bit and create more balance in this world,” he said.

His ultimate goal, he said, is to create a holistic wellness facility.

For now, he’s most looking forward to the Mindful Living Health Expo & AltaMed 5K he’s organized for Saturday, Jan. 31, at Los Angeles Memorial Coliseum. The free community event will include free health screenings, holistic wellness sessions, children’s soccer with the LA Galaxy, yoga classes taught by well-known instructors, including Mitchell, and a concert. The event is bringing in 5,000 school children from all over Los Angeles, and Mitchell hopes the community joins too.

“I’m just so excited about it, and it just feels right,” he said. “It feels like it’s [my] purpose.”