When it comes to competing Eliud Kipchoge and Sifan Hassan have nothing left to prove, so what drives them to keep showing up for elite level marathons? Ahead of a massive Sydney marathon, we put that question to these two champions, before asking Australian competitors Brett Robinson and Jess Stenson to help us understand what makes Kipchoge and Hassan so formidable. Featured: Eliud Kipchoge, marathon legend. Sifan Hassan, Olympic gold medallist. Jess Stenson, Olympian. Brett Robinson, Olympian. 

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