Transcript for Veterans team up with former athletes to build more than just physical strength
formed within the gym's walls. Reporter: 36-year-old David Rendon and 38-year-old A.J. Perez are more than sparring partners. They are brothers. Not biological but the type born through service to this country. A.J. Served in the Navy doing anti-piracy ops. David spent 12 years in the army, two of them in Iraq and Kuwait. They credit this gym with saving their lives. Unbreakable gym in L.A., gym to star clientele like Chris Pratt, wiz khalifa, and Sylvester Stallone. But according to the gym's owner and sports commentator, Jay glazer, their most important clientele are veterans. They're the smartest group of people you will ever be around. Every single week I leave here, I'll call and family and friends go, oh my god, you've got to hear what this vet said what that vet said. Two minutes left! Jay creates a program called MVP, merging vets and players to provide veterans and former athletes with a new squad. Started with NFL players, now spanning all sports, and ex-combat vets, you need to realize the uniform doesn't define you. Reporter: Our New York giants defensive end Michael Strahan is a board member and a volunteer here. Just guys that have a loss. They don't have that group to go to because your life was always so structured and regimented, and all of a sudden you're released into the world without the structure and the guys to back it up and talk to and communicate with. That's the challenge for most athletes and definitely for most soldiers. Reporter: Jay realized both veterans and former athletes were struggling to reacclimate to civilian life. A lot of these guys when they're done, they have the same statement that our vets do, I'm alone. You're not alone. Reporter: Once a week elite men and women descend upon this gym for an intense workout. Someone needs some help, someone needs to share something? Reporter: Followed by a peer therapy session. I myself have attempted suicide three times. Went there the bottom, now I'm here. The ultimate mission, number one, is 22 vets a day who commit suicide. I'm going to try to do whatever I can, use this big mouth to get people to know it's not okay. We're out here for you. Reporter: For many of the vets in this room, this has become their lifeline. You can't do it alone. And it doesn't mean that you're weak to ask for help. That's strength. Beautiful day. No clouds either. Reporter: David credits it with saving his life. I like coming up here. It reminds me of when I was depressed, cooped up, dealing with PTSD and anxiety. This tunnel kind of represents that dark period of time I went through. Reporter: After 12 years in the army, David was forced to retire. Injured in an accident, he was no longer deployable. You see stuff, you see things that stay with you. One day I just broke. All my symptoms just came. The sleepless nights, the nightmares, the cold sweats, the cramping. I didn't understand what was going on. I lost myself. Reporter: David was suffering severe PTSD and withdrawals from pain pills. What's the point of living like this? I was afraid that he was going to take his life. Reporter: It was his brother, ever, that took him to the V.A. To get treatment, but his troubles didn't end there. Slowly the depression crept back in. He began hiking as a way to keep himself occupied. But he couldn't keep the bad thoughts at bay. I didn't know where else to go, I didn't know what else to do. I was feeling lonely again. I needed that camaraderie again. That's where MVP came in. I can't describe it sometimes. This place is -- has done so much for my personal growth, mental health -- Reporter: It's here that David met A.J. A.J. Joined the Navy straight out of high school. When he left four years later -- That's I think when it hit me. I was like, I no longer have access to base. My entire world just disappeared. And I was like, oh. Reporter: Having never interviewed for a job, and not knowing how to write a resume, he really struggled to set up a new life. He spent the next few years bouncing between jobs, depending upon the kindness of friends to feed and house him. It really feels like quicksand. And it just feels like you're grabbing on to all these different branchs and each one just snaps and you're sinking lower and lower. Reporter: A friend introduced him to MVP. I checked it out and I fell in love with it immediately. I immediately recognized, this is my tribe. I finally found that branch. That one branch that I've been looking for for so long. I finally found it. Not only did I grab it, but it pulled me up. Reporter: He is now the program coordinator at MVP. Here you'll find the story of a changed life over and over again. One of the guys that I was deployed with in Iraq had committed suicide. And it really hit close to home for me. Because I'd been in that place less than a year before. I'm struggling to get my wife through what has been by far the hardest year in her life. Just got eight months over. What allows people to open up? You see a bunch of mostly men, women too, working out. Why do the walls fall down the second you guys all sit down together? After working out, when you go through something, when you sweat with somebody, do something that's difficult, you cheer each other on to not give. You're more receptive to opening and up saying, hey, thank you, I needed that today. All of a sudden it's a ripple effect. Reporter: That ripple effect extends far beyond the vets. When you see each other, it's family. Something about the commitment that you know you've had to make that not everybody's cut out to do. We are truly all brothers in one way or the other. You did it unselfishly so that guys like me and the rest of us could go out and run around in tight-ass pants and hit each other. I'm just happy and honored that we could be here to witness this. So thank you guys for letting us be a part of your day. Reporter: Humbled, overwhelmed, filled with great debt of gratitude. For "Nightline," I'm Sara Haines in Los Angeles.
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