成人快手

Whilst most of us will be fixated with the action on the track at the Rio Olympics, there's a a small select group focusing on what's happening in the stands.

John Roberts & Rita Ochoa from AFL architects, a firm that specialises in sport stadia, explained why to Sportshour's Shari Vahl.

Photo - Aerial view of the Olympic Stadium, known as Engenhao, which will host athletics and football events during the Rio 2016 Olympic Games (Credit - Getty Images).