Shaquille O'Neal recalls sportscasters criticizing him for his weight while playing in the NBA

It Figures is Yahoo Life's body image series, delving into the journeys of influential and inspiring figures as they explore what body confidence, body neutrality and self-love mean to them.

At 7-foot-1-inches, Shaquille O'Neal stands out in every room. Yet the basketball icon says he has struggled with how his body is seen.

"When you perceive yourself as looking good, you feel good," the four-time NBA champion tells Yahoo Life. "When you perceive yourself as not looking good, it can start to provoke some negative thoughts. … I take criticism all the time, and it doesn't hurt my feelings, but [Charles Barkley] used to call me fat on the air all the time, and I would go back and — I was really chubby. I don't like to use to those names, especially when it comes to other people, but I definitely was that."

O'Neal, now 51, says that he didn't take the sportscaster's comments personally, but they did make him take a hard look in the mirror.

"I'm the kind of person who, before I respond to criticism or I get emotionally involved, I see if there's truth in it. And there was truth in it," he explains. "It's not like I had a 12-pack…I went home and I wasn't in shape. I was in terrible shape. Bad shape. But I really didn't think about it, because my day was work. So what do you do? You create crazy motivation for yourself."

It's difficult to imagine a world-class athlete dealing with body image struggles. However, Riley Nickols, a sports psychologist and founder of Mind Body Endurance who is a member of the National Eating Disorders Association (NEDA) Clinical Advisory Council, says it's not surprising.

"Male athletes can experience both internal and external pressures to have bodies that are high in muscle and low in body fat," he explains. "The pressure for male athletes to have well-defined muscles, minimal body fat and a physique that conveys strength, power and athleticism can lead to maladaptive behaviors that put an athlete's physical and psychological health at risk. Achieving high athletic performance has long been the centerpiece for athletes. However, there now seemingly is pressure for athletes to both perform at a high level in sport and to 'look the part.'"

While that standard didn’t exist when O'Neal was entering the sport, he acknowledges that his upbringing in the projects of northern New Jersey contributed to a general lack of understanding when it came to nutrition and physical health.

"The only vegetable I knew was spinach [and carrots]," he says. "My parents used to say, 'If you eat your carrots, you won't go blind, and if you eat your spinach, you'll be as strong as Popeye.' But as I got older, I had to educate myself."

Now, O'Neal says, more NBA stars are hiring professional trainers and chefs, allowing them an opportunity to level up when it comes to their health, fitness and performance on the court. Shaq says he didn't have a professional chef until his eighth year in the league.

"I used to wake up, have McDonald's for breakfast, have McDonald's for lunch, play a game and then go to a restaurant," he shares. "But now, guys are really conscious of their bodies and have nutritionists. There's more understanding. If I had this internet stuff growing up, I'd be a genius by now. Back then it was like, ‘A nutritionist? What's that?' I'd probably still be playing."

According to Lorraine Killion, an associate professor in the Department of Health & Kinesiology at Texas A&M University-Kingsville, it makes sense that there has been a shift in how NBA players approach their bodies.

"The 'ideal' male body is viewed by society, coaches, trainers, athletes, as well as the media as a lean, but muscular physique," she explains. "Athletes are faced with the pressures to meet an ideal body specific to their sport. Whether they are appearance driven for leanness, muscularity or improved performance, athletes explore various venues for regimens of eating and exercise to achieve their desired body image. In many instances, it is an attitude of 'do whatever it takes' to achieve that goal."

For the athlete, achieving that ideal physique meant losing weight. He says he's dropped 40 pounds thanks to the products he endorses through his partnership with Novex Biotech®. Dr. Claudia Ramirez Bustamante, fellow physician of medicine-endocrinology at Baylor College of Medicine, says that the clinical trials cited by the company regarding their weight loss supplements are "questionable," with the main concerns being the small sample size.

"To the best of my knowledge, no clinical trials have been initiated to assess the long-term effects of this supplement," Bustamante tells Yahoo Life.

Yet while O'Neal may feel pressure to look a certain way, he also strives to achieve his goals by setting the same boundaries for himself that someone without a reported $400 million net worth might have.

"I like to position myself as the every day man," he says. "The every day man can't afford a trainer. The every day man can get a gym membership and do cardio and some weights. I try to get cardio in all the time and I try to lift some weights. I don’t run and jump and do all that extra stuff. The average man has to work a 9 to 5, they have to carve out that hour."

"Every day I try to get an average of 30 minutes to an hour of cardio," he explains. "If you do that and eat really good — not perfectly, not the foo-foo diet, I'm not a foo-foo diet guy, if I want a sandwich, I eat a sandwich — but, you know, I try not to cheat twice a day."

Ultimately, this routine allows Shaq to feel his most confident as he manifests his next career moves.

"Now, I want to do an underwear ad with [my sons]," he says.

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