SAN FRANCISCO (CBS SF) — When the paparazzi caught Jennifer and Joe Montana frolicking in the water while vacationing in Maui, they exposed what may be the couple’s sexiest secret. Mrs. Montana’s body looks amazingly hot — in a bikini!

The cameras don’t lie. A beauty, at age 56, Jenn has washboard abs.

What’s her secret?

“Joe will tell you I don’t do a thing, its just genes, but that’s not true,” explains the former actress.

She said keeping up with her 4 kids used to be enough of a workout. They’re all grown up now.

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“Now I work out to maintain… to keep my heart going,” she says. “Since they are gone, it’s 3 days a week, when I can fit it in.”

As for dieting?

“I don’t diet, and maybe that’s where the genes come in — I don’t seem to have to.”

Jennifer does concede one thing when it comes to her food regimen, and it’s something everyone can do.

“I have good eating habits,” she says. writer, producer Jan Mabry is also executive producer and host of The Bronze Report. She lives in Northern California. Follow her on Twitter @janmabr.