Josh Holloway pleaded with his Lost writer pals to give him five days' notice when he had to strip off on camera - so be could keep his beer belly in check and work out to look good.
The actor admits his love for food and beer became a problem on the Lost set in Hawaii because he struggled to stay in shape and so he befriended the guys behind the script in a bid to stay one step ahead of the director.
He explains, "All my brothers were skinny with a gut... That's what I fight against. I love food, I love drink, I love that social thing.
"They (writers) would give me five days' notice... Writers and producers expect you to be in shape all the time, but as they became my friends, I'd say, 'Dudes, give me a little warning...' Then I'd warrior up, do more weights, and stick to eating steak and fish."
But Holloway had to get serious about his physique when he got a call to join Tom Cruise in the new Mission: Impossible movie and he lost 20 pounds (nine kilograms), which he now intends to keep off.
He tells Men's Fitness magazine, "No more of that desperation push (before topless scenes). I'm going to stay fit. It feels better."