Rebel Wilson is aiming to lose 165 pounds

As well as wanting to slim down, the 40-year-old actress is also hoping to get one of her movies into production, and though she admitted she faces "constant setbacks", she's doing everything in her power to succeed.

Alongside a snap of herself in her gym wear in her living room, Rebel wrote: "Even if you have to crawl towards your goals, keep going x it will be worth it. Try and give a little bit of effort each day…I know some days are frustrating as hell, you feel like giving up, you get annoyed at the lack of progress…but good things are coming your way.

“What are your goals this year? I’ll be honest with you guys – with my ‘Year of Health’ mission I’m trying to get to 75kg’s (165 pounds) and career wise am trying to get one of my movies into production before the end of the year!

"Both of these things are requiring a daily effort and there’s constant set backs – but I’m working hard. (sic)"

Last year, Rebel revealed she lost eight pounds in just four days performing the dance scenes for 'Cats'.

The 'Isn't It Romantic' star believes she shed the weight quickly because the studios they performed in were heated so high it was "pretty uncomfortable" and because of the intense "physicality" of the routines.

She shared at the time: "I lost eight pounds, shooting my number, in four days. One, because there's a lot of physicality ... but also, they heated up the set very high, to almost 100 Fahrenheit, so that we could never cool down. These people are like, the best dancers in the whole world, so they can't cool their muscles down or they could get an injury and they'd be out of the film ... So they'd heat up the set like a sauna so we would never cool down, but made it pretty uncomfortable."

Rebel played Jennyanydots in the Tom Hooper-directed adaptation of Andrew Lloyd Webber's musical classic, and she quipped that: "Apparently, I was deemed the naughtiest cat at cat school."