"Something inside of me changed," Arnold, whose top weight was 287 pounds, told People.com about becoming a father. "I knew I needed to live as long as I could."
The 54-year-old former "Roseanne" cast mate and "True Lies" co-star said he felt "a lot of shame" about his size over the years.
"One time I had a tailor come over and sew the weights into my suits -- this is what you wear when you are 210, 220, 240, 300. That saved me the time of going into my closet and getting so upset and frustrated," Arnold told People.com.
"The moment I saw [Jax] I realized he deserves the best," Arnold said, adding he first gave up bread and cake, and now does regular cardio, circuit-training and abdominal workouts.
"I have tons more energy to play with my son," he said.
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