Mum-of-one Abby Pell works as a nutritionist and is a dedicated fan of weight-lifting - and, as a result, has a six-pack stomach.
But while 33-year-old Abby had hoped her fellow mums would find the photograph inspirational, she was accused of "fat shaming".
One Instagram user wrote: “Another unrealistic expectation to put on new mothers?”
Another fumed: “Life is too short to be self obsessed beauty is from within and if people don’t like you for who you are then they’re not worth knowing.”
But, despite the backlash, Abby has insisted that, while she did not intend to pile pressure on new mums, she does think they should continue to work on their bodies.
She told The Sun: “Having a child is not a valid reason for being out of shape.
“Everybody can make excuses. I want to show that this figure is achievable.
“It doesn’t matter if you’re overweight, if you have a busy lifestyle and kids to look after — if you want to do it then there’s always a way.
“Being a mum doesn’t mean you have to give up. You can have stretch marks and a great figure.”
She added that she believes some of the nasty comments she received were down to jealousy, saying: “I’m not saying the nasty comments are jealousy but it might be that these people are insecure in the way that they look.
“Some people want to be able to make excuses and don’t like it when an alternative body type is put in their face.
“In an ideal world everyone would be happy and confident in their own skin regardless of their shape or size. But unfortunately that’s not the case.
“I want to appeal to those who want to change but don’t think it’s possible.”
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