When Kate Champion put an ad on social media calling for "fat dancers" for her next show, she got a mixed reaction. Some people immediately pounced, accusing the Australian choreographer of being voyeuristic and exploitative. Others asked: how fat do you have to be to audition? Champion even received queries from size 10 women.

The dance-maker was conscious of offending people by using that loaded little word in the call-out, but she wanted to be direct. "We did say fat. We asked for people who identify as fat, larger, big-bodied."

Champion is making the production with artist and fat activist Kelli Jean Drinkwater. "You can't make a simple work about body size because it's an incredibly complex conversation," she says. "I personally use the word fat because I've reclaimed it and it doesn't have any negative baggage. It's just a description of my body, like tall or brunette. But not everyone is at that point, and we wanted to make it feel like a very welcoming call-out: we wanted people to feel safe to put themselves out there. On the other hand, we're not shying away from this subject. We wanted actual fat people in this work, not necessarily just curvy."

Luckily, the controversial idea resonated with enough people, and the pair received plenty of audition videos from larger dancers. "A lot of people ended up filming on their phone in the hotel room they happened to be staying in, or in their living room, so that was quite sweet because it felt private, but it was for us," Champion says.

The resulting contemporary dance piece, Nothing to Lose, will premiere at Sydney Festival in January. Dancers are usually slim and muscular; this show aims to create a completely different look on stage, exploring how bigger bodies move. Champion wants to question the dominant idea of what a dancer should look like by presenting confident and talented plus-size performers.

"For all we say about there being more representation in contemporary dance, I don't actually think there is," she says. "My company, Force Majeure, has always endeavoured to represent its audience on stage in some way. But dancers' bodies, as amazing and skilled as they are, can be quite alienating. We want this show to have a strong visual impact: it's undoubtedly about the larger body."

Featuring five women and two men, Nothing to Lose promises to be energetic and lively, with movement ranging from flirtatious and sensual to grotesque and humorous. It's partly inspired by the dancers' experiences and relationships with their bodies. The cast are not professionally trained dancers, but they all have backgrounds in performance.

"It's about charisma, personality and how they are when they move," Champion says. "I'm more interested in people who are very captivating movers, who have an authenticity and ownership of their bodies that is compelling to watch."

But Champion is keen to make sure the production won't be a voyeuristic experience for the audience. "And I'm very careful that it's not a freak show. We want there to be humour but we don't want the dancers to be laughed at. And if they are laughed at, we want to turn that back on the audience and question it. We want to be intelligent about how we use the audience's gaze on this body shape… and all the opinions and judgements that seem to be inherent in that."

At a short, 15-minute preview of the work this summer, an audience member questioned whether the dancers would be able to last the hour-long production. "There was this incredible instant assumption that they won't have stamina," says Champion. "We know these assumptions that people make, but we're trying to get ahead of that, not bend towards what everyone is obsessed about, and try to make it an example, display and celebration of who these people are."

Attempts to feature larger people on the dance stage are few and far between. The Channel 4 documentary Big Ballet cast plus-size amateurs in Swan Lake, and the occasional contemporary troupe embraces more diverse body shapes. But Champion and Drinkwater are largely navigating uncharted territory.

"We feel confident in what we're doing," Champion says, "but at the same time we feel we need to brace ourselves. Because people are ready to attack so quickly just based on assumptions about what we're trying to do."

Certainly it's a very charged issue, and one that's personal to many people – but Drinkwater says that's what makes Nothing to Lose vital. "There's an increasing interest around body politics. People are – if you'll pardon the pun – hungry for a different view of this conversation. It's a work about fat people made by fat people with a clear aim to address the complexities of these issues, not just the one-dimensional 'fatty' view on things."