The parents to son Axl, 3, enjoyed some beachside fun during a vacation in Kihei, Hawaii on January 1.
Fergie, 41, gave a peek of her toned tummy while wearing a navy blue bikini, colorful sheer cover-up, wide-brimmed hat and sunglasses while flashing a smile on the shore, while Duhamel, 44, enjoyed some time in the water in blue swimming trunks that showed off his hot-dad bod.
The couple — who tied the knot in 2009 — help motivate each other in the gym.
“She’s definitely more competitive than [I am],” Duhamel told PEOPLE in 2011. “But it’s all in fun. She’s likely to say, ‘Let’s do one more mile,’ and every time she finishes a workout she says, ‘The glory is mine!’ meaning she actually got up and did it.”
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“We motivate each other. She pushes me, and I push her,” he continued. “It’s something that we’ve always done for each other, whether it’s working out or in our life together. We’re compatible in that way.”