By Mark Trevelyan

RIO DE JANEIRO (Reuters) - Double Olympic champion Ashton Eaton threw out a challenge on Thursday to come up with ways to make the decathlon more exciting, suggesting that most spectators fail to grasp the intensity of the arduous event.

Spread over two days, the decathlon tests the attention span of sports fans and is based on a complex points system that computes the athletes' total rankings across 10 track and field disciplines.

"I think there is a way to make this event and the (women's) heptathlon also wildly more exciting than it is for spectators to watch," the 28-year-old American said after clinching his second consecutive Olympic decathlon gold medal.

"I don't have time to think of the way, because we're training. But somebody should because ... I don't know, it's just awesome.

"One of the best tweets I saw I think was (comedian) Bill Murray, and he said we should put an 'Average Joe' in every event to give a reference. He was talking about sprinting and all that but that'd be pretty sweet to see in a decathlon."

Bronze medalist Damian Warner of Canada, addressing the same theme, told reporters one factor that dampened fans' enthusiasm was that decathletes cannot match the performance of those who specialize in a single event.

"So we throw the shot put 14 meters and they throw 22 meters, and they think 'that's not very special' or you see us run 1,500 (meters) in 4.20 and we are lying on the ground dying, and people out there can run it a lot faster," he said.

"But think what people don't understand, and the kind of lack of education that Ashton was talking about ... we have a very small amount of time to work on those events, and we are doing 10 different events.

"I think that's where the 'Average Joe' thing could come in and people could see how tough it is. Once people see how tough it is, they get a lot more excited."

(Reporting by Mark Trevelyan and Drazen Jorgic; Editing by Mark Lamport-Stokes)