(CNN) -- There is a lot to be said for enjoying the work that you do.
"Downtime would probably just get me into trouble," Freddie Roach said jokingly.
Roach, one of the most sought-after boxing trainers in the sport, loves coming to work each and every day, and he says it's that passion that helps him deal with Parkinson's disease.
"I have a job I like to go to, and not everyone in the world can say that," he said.
The five-time trainer of the year has worked with the likes of Mike Tyson, Oscar De La Hoya and James Toney. But his star pupil by far is current World Boxing Organization welterweight champion Manny Pacquiao.
Roach, 51, is a former boxer but he admits his career didn't go exactly the way he envisioned it.
"I put everything into this sport and didn't get much out of it," he said. "I was a little frustrated with my life."
He retired in 1987 after 54 professional bouts and became a trainer later that year. The Parkinson's diagnosis came a few years later.
"I've been on medication since 1992, and I've been holding my own," he said. "I've been very functional."
Whether boxing contributed to or caused Roach to develop Parkinson's disease is unknown. Roach and his doctors say his condition could have been trauma-induced. But Parkinson's disease also runs in Roach's family.
The tremors and rigidity associated with Parkinson's disease have progressed slowly in Roach, in part, he says, due to the physical nature of his job.
"It's fun to be busy, because it keeps me from letting the Parkinson's take over. The hand-eye coordination stuff that I do with the mitts and so forth, it's the best thing in the world to fight Parkinson's," he said.
Roach credits former heavyweight boxing champion Muhammad Ali and actor Michael J. Fox, both of whom have Parkinson's disease, with raising awareness and money for Parkinson's research, and he says he's confident a cure will be found in his lifetime.
Roach admits that he gets frustrated with his condition at times, but he quickly snaps out of it. "I don't want anyone feeling sorry for me. I have a great life."
With 31 world champions on his résumé and a recent election into the International Boxing Hall of Fame, Roach says, staying busy and doing what he loves is the best medicine for him.