The 10-time Olympic medallist was at an all-American event in central London as the USA team came together on the eve of the Opening Ceremony.
With just hours to go until the Games get under way, he tried to sum up what is so special about the event.
'The Olympics is the only event where the world stops. The world stops. It's global. Everyone is allowed.
'If you're the smallest country with the fewest people in the world or the biggest country with the most people in the world, everyone's allowed and everyone is invited, so it's a great thing because you get to see the world and the world sees you,' he said.
Shannon Miller, the most decorated gymnast in USA history, was also in attendance, but the seven-times Olympic medallist said it is not all about winning.
'I think what separates the Olympics from any other sporting event out there is maybe the passion.
'Everything else slides away. It's all about sport. It's all about triumph over tragedy.
'It doesn't matter whether you walk away with a medal or not, you're an Olympian when you leave London.'
