EXCLUSIVE: Gwen Stefani and Blake Shelton Dish on Hitting the Gym Together: 'He's My Trainer!'

Gwen Stefani and her boyfriend, Blake Shelton, are spending time together by hitting the gym for some morning workouts.

Stefani and fellow Voice coach Adam Levine spoke with ET's Sophie Schillaci in a Facebook Live interview at the NBC singing competition's live show on Tuesday, and the "Used to Love You" singer dished on spending time exercising with her country crooner boyfriend.

"He killed the gym this morning," Stefani marveled. "It's funny because he’s so tall that like, literally no sweat suits fit him."

WATCH: Adam Levine Calls Blake Shelton and Gwen Stefani's 'Voice' Arguments Like a Sportscaster

Levine, however, had a hard time believing his longtime co-star and friendly rival would even step foot in a gym.

"I feel like you'd be there for five minutes and he’d be like, 'I'm havin' a heart attack!'" Levine joked.

"Actually, it's because of him that I worked out this morning," Stefani explained. "I wasn’t gonna work out… He's my trainer."

WATCH: 'The Voice': Blake Shelton Gets Jealous as Gwen Stefani Fawns Over Singer: 'I Was Mesmerized By Your Body'

The No Doubt frontwoman took to Snapchat on Tuesday to share a few pics and videos from their workout adventure, writing that the couple "Man handled the gym today."

As much as Stefani seems to love it, getting healthy appears to be taking a toll on her boyfriend.

"I get hurt in the gym every morning," Shelton quipped while talking with ET alongside fellow coach Alicia Keys.

PHOTOS: Gwen Stefani and Blake Shelton's Cutest Moments

Shelton also said Stefani doesn’t really need to work out. "I mean look at [her]. Wouldn’t you like to be born with her genetics? It’s not fair!"

For more on how Shelton and Stefani's adorable relationship is playing out as they go head to head on this season of The Voice, check out the video below.

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