Mike Tyson's gruelling "100-pound process" to get in shape for Roy Jones Jr. fight

After 15 years in retirement, Mike Tyson will return to the boxing ring tonight to face Roy Jones Jr. During his preparation, he started to train again to get back in shape after putting on a lot of weight during his retired years. The former heavyweight champion has explained how he got back to hitting mitts.

"It's a 100-pound process. My wife told me, she pretty much asked: 'do the treadmill 15 minutes a day.' So that 15 minutes turned into two hours a day. From there, I started doing two hours on the treadmill, an hour on the bike. Then I started running. I don't know where I was. I wanted to hit the mitts. I don't know why I wanted to hit the mitts, and someone said they knew Rafael Cordeiro, and he held the mitts for me." (H/T: MMA Fighting)

Rafael Cordeiro is the mastermind behind the return operation. The Brazilian MMA coach has received innumerable awards and honors for his coaching and training techniques. He has also been the coach of UFC legends such as Lyoto Machida, Fabricio Werdum, Wanderlei Silva, and Mauricio "Shogun" Rua.

Mike Tyson has also spoken about the psychological challenge of getting back in shape when you're out of experience.

"When I was hitting the mitts, I believe we showed it on Instagram, and it got over like 2 billion hits. Before that little 20 second combination, I was in bed for six weeks; I was all messed up. I got comfortable with the process of punching and moving and then eventually sparring. I'm never calling another fighter a bum again because the process of getting in shape to fight somebody is just psychologically overwhelming if you're not an experienced fighter."

Mike Tyson knows he can't compare his form now to his form from any point of his professional career, even at the low stages. However, "Iron Mike" seems happy to admit he is in a much better place now mentally than he has ever been in his life, especially if compared to when he was young.

"I never put myself in that perspective because I didn't know what I was then. I'm just very more comfortable in the way who I am now to a certain degree. Not totally, but to a certain degree. So I can't compare the two, but this is what I want to do. In my last fight, I didn't have no interest in doing it. I'm interested in doing it now."

Because Roy Jones Jr. and Mike Tyson are both over 50 years old, there's an undeniable concern regarding the athletes' well-being during the fight. The California State Athletic Commission has put in place a set of rules to ease the duel's violence. However, both former champions know that if they are boxing for real, as they say they are, then it is hard to control what happens in the ring.

"Maybe I don't know how to go easy. I don't know. I don't want to say the wrong thing cause some people get angry, the boxing commission, so I don't want to say the wrong thing. I'm just going to go right at him as soon as the bell [rings]. We're just going to see what happens. Listen, from any perspective, how they look at it, it's going to be entertaining. I'm a fighter, he's a fighter, and of course, we're in there throwing punches. During that process, anything can happen."

Mike Tyson's career in hindsight

Mike Tyson's career is full of ups and downs. The American was once considered "the baddest man on the planet", a title he didn't get for nothing. Tyson shocked the world by winning his first heavyweight title at just 20 years old back in 1986.

A Look at Mike Tyson's Career Earnings

As he started to compete professionally two years earlier, Mike Tyson won his first 19 boxing matches by knockout, 12 of them in the first round. After a winning streak of 37 fights, "Iron" Mike Tyson was finally defeated in 1990 by Buster Douglas, in what is considered one of the biggest upsets in sports history.

After that, Mike Tyson's career started to erode. He was still displaying out-of-this-world boxing skills, but would often show signs of disinterest. Rumors about his lack of training were always present. However, the worse came when his tutor and mentor Cus D'Amato passed away.

Mike Tyson would then be in constant problems with both the law and the boxing world. He was even once disqualified for beating up the referee, while Tyson's most infamous sporting moment would be biting Evander Holyfield's ear off.

In another low point, Mike Tyson would transform his last professional fight into a disaster. He gave up fighting Kevin McBride in the seventh round and went on to admit his heart wasn't in it anymore.

"I don't have the stomach for this anymore. I most likely won't fight anymore. I'm not going to disrespect the sport by losing to this caliber of fighter."

Mike Tyson vs. Roy Jones Jr. will take place tonight in California. Find out how you can watch or stream the fight here.