Tammy Hembrow insists her famous derriere is the result of 'hard work' as she shares extraordinary before and after photos – but her followers aren't convinced

Fitness guru Tammy Hembrow has long denied rumors that she underwent a Brazilian bum lift to achieve her famously tight derriere.

And the mother-of-three, 29, reminded her 17.6 million Instagram followers on Thursday that her curves are the result of hard work.

'I don't think I've ever been as excited about a challenge as I am now. When I tell you I NEED this challenge, she wrote while promoting her popular workout app Tammy Fit.

Tammy continued, “After indulging way too much and having a little too much time off, I'm so ready to see some big results.”

But while the influencer tried to convince her followers that her transformation was the hard work of diet and exercise, her fans thought otherwise.

And on Thursday, the mother-of-three, 29, reminded her 17.6 million Instagram followers that her results influence the results of hard work as she promoted her popular workout app Tammy Fit (Picture: Before and After)

Despite her assurances, Tammy's post was met with a wave of skepticism among her followers.

The responses poured in, with one insisting on authenticity.

'You've been doing this for over 8 years? Be more authentic when promoting your products :(' they wrote.

Another added bluntly: “Cough-cough surgery.”

Despite her assurances, Tammy's post was met with a wave of skepticism among her followers

Meanwhile, questions resurfaced about whether Hembrow had undergone a Brazilian butt lift (BBL), with one asking: 'No hate Tammy, but didn't you have a BBL?'

Meanwhile, questions resurfaced about whether Hembrow had undergone a Brazilian butt lift (BBL), with one asking: 'No hate Tammy, but didn't you have a BBL?'

Another followed: 'But you also had surgery, I saw that.'

Tammy has previously revealed that she 'hates' it when people falsely accuse her of having a Brazilian butt lift.

Tammy insists she has developed her bum thanks to strength training, and says she can perform 60kg squats. In the photo on the left in 2014 and on the right in 2019

She said during an interview with Studio 10 in December 2019: 'I hate it when people accuse me of that.

“I take such offense because I've worked so hard and it irritates me.”

When asked how she maintains such a rounded backside, Tammy said it all had to do with strength training.

'I do a lot of heavy weights. You're not going to build muscle if you don't do leg weights,” she explained.

“I see a lot of girls doing cardio and this and that, (but) it really doesn't build any muscle.”

Tammy has previously revealed that she 'hates' it when people falsely accuse her of having a Brazilian butt lift. She said during an interview with Studio 10 in December 2019: 'I'm so offended by it because I've been working so hard and it irritates me'