How Randall Park Changed His Life After the Death of His Father: 'A Wake-Up Call' (Exclusive)

Randall Park has faced some of his greatest personal challenges in the past few months.

“The last year has been a lot of highs and a lot of lows,” The Residence actor tells PEOPLE exclusively. Witnessing his father’s death from cancer in May 2024 — and turning 50 a few months prior — led Park to reassess his own health.

"Seeing my dad, his health ailing, and his body breaking down was very much a wake-up call for me," Park says. “I have a daughter, Ruby. She’s 12 and on the autism spectrum. Just wanting to be healthy as long as possible, to be there for her as long as possible, really hit me.”

So he got to work. Park began training and ran his first marathon in New York City in November — something he says never crossed his mind until he was approaching his 50s.

"That's part of the reason why I decided to sign up for the marathon, to give myself a goal, and to also prove to myself that even at this age, I can do hard things," Park, now 51, explains. "That was the spark for me."

He trained for the big race by researching and running with friends. Despite having fears about hitting the dreaded "wall," he never did.

"I was very conscious about fueling during the run, making sure that I stayed hydrated throughout, and was very meticulous about those things," he recalls. "When I ran it, my goal was to just finish it first off. In any way, just finish it. My other goal was to not stop or walk. I just wanted to run continuously [and] I was able to do that."

Though his days can be "unpredictable" due to his busy schedule, Park — who is starring in Netflix's new murder mystery The Residence and CBS’s Watson, where he plays the iconic Sherlock Holmes villain Moriarty — is strict about fitting in a workout, even if it has to be broken up into multiple parts throughout the day. He keeps a fitness journal, where he jots down any injuries he's suffered and the progress he's noticed.

The Fresh Off the Boat alum admits he's still "pretty bad at the nutrition aspect," but he's always naturally leaned towards "protein-heavy meals" with "a lot of greens and vegetables."

"I don't eat a lot of sugary things," he adds. "I just was never too big of a dessert person."

Though does candidly admit: “Last night, I had pizza. I’m more mindful than strict.”

Park’s new workout routine also has given him a mental health boost.

“I have more energy to be physically active and fit, but it’s for my mind as much as it is for my body. It keeps me optimistic and upbeat,” he says. “It’s also been really fun. I probably wouldn’t stick to it if it wasn’t.”

Another thing he's having fun doing right now is starring in the Shondaland whodunit as special FBI agent Edwin Park, alongside Uzo Aduba as Detective Cordelia Cupp, who launches an investigation after a dead body turns up in The White House during a State dinner.

"It's just a really fun show," he says of The Residence. In addition to "adoring" working with Aduba, he gushes about the "stacked" cast, which also includes Giancarlo Esposito, Susan Kelechi Watson, Jason Lee, Ken Marino and Bronson Pinchot to name a few.

"It's a rare thing, but everybody on the show is just so lovely. We all just became very close," he says. "To this day, we are all friends, we keep in touch, we have a text chain going. When we're in each other's cities, [we'll] grab lunch. It was such a lovely experience with so many great people."

As Park approaches the first anniversary of his father’s death, he hopes for the “continued good health” it inspired as well as opportunities to do "more things that I haven’t done before,” he says.

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"New opportunities, colleagues and friends. That's one of the great things about what I do, is I get to meet new people all the time," he continues. "It's just a pretty incredible thing to be in your 50s, and to be making new friends."

He'll also take more of the simple things in life, like spending time at home with his daughter and wife Jae Suh Park. "To just really be happy," he says. "Be as happy as possible."

The Residence is now streaming on Netflix. Watson airs Sundays on CBS at 9 p.m. ET/PT.