The Russian duo of Natalia Ishchenko and Svetlana Romashina are the favourites to maintain their country's place at the pinnacle of the sport, having been both Duet and Team champions since Sydney 2000.
According to the 15-time world champion Ischenko, hard work lies behind Russian success.
She said: 'We train more than 10 hours a day.
'We have the best coaches and specialists in the world and thank God they still live in Russia.
'It's also about talent, it's about soul.
'The Russians are very good at ballet and gymnastics because the Russian soul is about living the music and living the dance.'