Rebel Wilson shows off her 18kg weight loss as she completes an arm workout while on a yacht

Slimmed-down Rebel Wilson shows off her 18kg weight loss in a red dress as she completes a hilarious arm workout using a bottle of vodka on a yacht in Monaco

She vowed to focus on her health and make ‘positive changes’ in 2020.

And on Sunday, Rebel Wilson made sure to keep up her exercise routine while on a relaxing holiday with her new boyfriend Jacob Busch in Monaco.

The actress,40, showed off her slimmed-down figure in a red dress as she completed a hilarious arm workout using a 4.5L bottle of vodka while on a yacht.

Working out! Slimmed-down Rebel Wilson showed off her 18kg weight loss in a red dress as she completed a hilarious arm workout using a bottle of vodka on a yacht in Monaco on Sunday

In the video shared to Instagram, Rebel told her followers: ‘Hey guys I’d like to show you my new workout routine. Basically we are just going to work the biceps.’

She started lifting the bottle towards her chest and back down, before carrying the heavy glass bottle over her head.

‘Just slightly bend your knees. You just really want to feel that burn,’ Rebel told her followers.

The Pitch Perfect star then held the bottle over her shoulder and joked:’And then you run up and down the stairs… and then that’s basically your arm workout for the day.’

Smashing goals: She started lifting the huge bottle towards her chest and back down, before carrying the heavy glass bottle over her head

Smashing goals: She started lifting the huge bottle towards her chest and back down, before carrying the heavy glass bottle over her head

Rebel looked stunning in a red Gucci minidress, complete with white borders and embellished gleaming gold buttons. 

She styled her long hair half up half down and wore a neutral palette of makeup for the trip.

The Hollywood star has been on a health and fitness journey this year, losing at least 18kg (40lbs or 2.8 stone). 

Hilarious! The actress then held the bottle over her shoulder and joked: 'And then you run up and down the stairs... and then that's basically your arm workout for the day'

Hilarious! The actress then held the bottle over her shoulder and joked: ‘And then you run up and down the stairs… and then that’s basically your arm workout for the day’

Rebel’s post comes after she shared a short clip while cuddling up to her 29-year-old businessman beau Jacob on the yacht.

The actress snuggled close to her handsome man, curling up with a blanket around her shoulders. 

The beauty made her red carpet debut with Jacob at a gala in Monaco last week.

What a transformation! Rebel has been on a health and fitness journey this year, losing at least 18kg (40lbs or 2.8 stone)

As you were: Rebel is pictured in December 2014 when she had a fuller figure

What a transformation! Rebel has been on a health and fitness journey this year, losing at least 18kg (40lbs or 2.8 stone). Pictured left on Sunday, right in December 2014 

So sweet: Rebel's post comes after she shared a short clip while cuddling up to her 29-year-old businessman beau Jacob on the yacht

So sweet: Rebel’s post comes after she shared a short clip while cuddling up to her 29-year-old businessman beau Jacob on the yacht

Jacob’s family founded the Anheuser-Busch brewery, which produces America’s most popular beer, Budweiser. 

In 2016, Forbes listed the Busch family as the 16th richest in America, with a fortune of US$13.4billion.

Jacob and Rebel’s 11-year age gap shouldn’t be a problem for the 29-year-old, who previously dated Real Housewives of Beverly Hills star Adrienne Maloof, 59.

Successful: Jacob's family founded the Anheuser-Busch brewery, which produces America's most popular beer, Budweiser. Businessman Jacob is readying the launch of his premium ice cream company called Napp's

Successful: Jacob’s family founded the Anheuser-Busch brewery, which produces America’s most popular beer, Budweiser. Businessman Jacob is readying the launch of his premium ice cream company called Napp’s