At 6 feet 6 inches, 260 pounds, Jameel McCline looks every bit as imposing and in fight-night shape at age 44 as he did during the prime of his 17-year roller-coaster ride as a professional boxer. And yet, the Delray Beach resident can quickly put a complete stranger at ease with his affable charm and disarming candor.

That McCline can be such a walking contradiction will come as little surprise to anyone familiar with a story that’s larger than life in more ways than one.

After all, this is the same man who started boxing at age 25—with no amateur experience—yet still fought for the heavyweight championship of the world four different times (he lost all four bouts, two of them by controversial decisions). The same man who barely made it out of Harlem, serving five years in prison for selling stolen guns after aging out of the foster system, yet went on to travel the world—including more than a dozen trips to Russia. Who, after his first retirement from boxing in 2009, was sweeping the floors of an automotive center in Boca.

Now, he’s driving a Mercedes and launching projects that fit neatly under the banner of his nickname in the ring—Big Time. Here’s more from our interview with the man who’s running in the Democratic primary later this summer for Florida’s 20th congressional district.

On his work as a consultant and training adviser for athletes in other sports:

• “I talk to them about something like social media. Don’t take pictures with booze in your hand. It doesn’t look right, especially if pictures like this pop up four, five, six times. Little things like that can impact reputation, endorsements. You also don’t want to use foul language on Twitter; again, it doesn’t come off right. … I had some NBA clients who were loud mouths. And I told them, being a loud mouth is one thing. Being disrespectful is something else.”

• “A lot of what I walk these guys through is recovery. My theory is this. As an NFL player, you get all banged up on Sunday. Monday is a day of rest. Tuesday, you’re just starting to recover from the game. Wednesday, you can start moving again. You can’t get physical in practice until Thursday. … I work with players on healing: the use of hyperbaric chambers; compression socks and sleeves, which promotes inflammation reduction; foods, antioxidants, legal supplements, protein shakes. It’s all about recovery. … If you can get back on the field at 100 percent by Tuesday, instead of Thursday, you’re two days stronger than all the other players.”

On why so many boxers have trouble holding onto their money:

• “Out of all athletes, boxers are often the least educated. You need to be educated in order to have an understanding that life goes beyond boxing. How are you going to handle that? … There’s a very small percentage of us that make it out OK. You’re world champ one decade; the next decade [you’re] living in a one-bedroom apartment. … I’ve been blessed to have an entrepreneurial sense about me. I shake hands, I meet people, I make things happen.”

On his boxing career:

• “I have a love-hate relationship with boxing for so many reasons. I gave me a lot, but it took a lot out of me. It destroyed my first marriage; it destroyed my relationship with my two other children, who live in West Palm Beach. I had a lot of mental issues, and part of it was being so hard on myself for not becoming champion. … It’s so rare to even get a title shot. It’s unheard of to get a third title shot, having not won either of the first two. It’s unprecedented to get a fourth—and you didn’t win any of the first three.

The flip side is that it gave me a career. It gave me an understanding of what it takes to be focused, determined … it taught me about sacrifice. I traveled the world—I fought in Russia, China, Poland, Switzerland, Mexico, Madison Square Garden three times. …

The universe just didn’t have it in the cards for me to be champion. Maybe it’s to go on and do other great things. There’s something else that I’m meant to do. I’m OK with it now.”