Cena recently teamed up with a footwear brand in order to encourage people to embrace their differences. In an interview with CBS News, he says that the reason he wanted to be part of the campaign was, "to showcase not only my childhood past and what got me into the realm of physical fitness, which eventually led me to define myself, but also the current state of affairs."
The athlete, who is engaged to Total Divas star Nikki Bella, added that he's had to endure a lot of criticism throughout his career. While many might look at his life and say, "everything's great," he shares that "there's a lot of struggle involved, and I'm just making a conscious effort every day to be a better me."
In May, Cena shared his experience of being bullied as a kid.
"I remember the walk to the school bus, at the very least, five times, shoved down, toppled down," the actor said in a promotional clip for Crocs. "I asked my dad, ' Is it okay if I start working out?' By the time I showed up at high school, I was big. The guys who were pushing me down were kind of like, 'We cool?'"
Cena adds that "never once" did he get back at any of the bullies because "as horrible as a time as it was for me, it was a catalyst for me to find a passion of my life." Adding, "Everyone goes through those moments of self-doubt."
Now that he's older, the Trainwreck actor says that he deals with negativity in a different way and can "reassure people that it's not the end of the world."
"I'm 40 years old, I've been dealing with this for almost two decades, but to a 12-year-old kid who's being cyber-bullied or a 20-year-old individual who's really trying to find their way in life, it's not as easy," Cena explained. "I'm in a different place now than I was 20 years ago, 30 years ago, so I guess from a level of experience I can reassure people that it's not the end of the world, and first and foremost be proud to be yourself, because that will set you up for the next 20 years."
For more on how Cena deals with bullies, watch below.