The challenges must also be difficult, exciting to watch and safe. "Absolutely everything is totally checked over and over and over again. We can't afford to put these people at risk," assures Keoghan. "It's perceived danger. To me what really works about the Race is not when we put people in harm's way. It's when they're pushed outside their comfort zone. Watching ordinary people in a totally unusual, extreme situation is interesting TV."
Doganieri is among the challenge testers, and vividly recalls a 134-meter bungee jump she made in New Zealand a few seasons back. "I'd never done that and I'm a little afraid of heights. I took about four minutes before I stepped off. I knew if I was that scared we had to do it for the show. But I almost had a heart attack doing that one," she admits.
In the event of a real medical emergency, contingency plans are in place. "We have first aid, and we know all the hospitals and have doctors on call. We have ambulances standing by," says van Munster. There have been a few mishaps. A rescue boat in Vietnam hit a sandbar, injuring a producer, and another producer broke her wrist. Several contestants have been hurt, though not seriously.