You can even observe cycles with just two players. In Cambridge (UK), the River Cam is too narrow for side-by-side racing over more than a few hundred yards.

You can even observe cycles with just two players. In Cambridge (UK), the River Cam is too narrow for side-by-side racing over more than a few hundred yards. Instead, a popular kind of racing has developed called "Bumps". Crews line up along the river with about a boat and a half's length between each other. At a signal, all crews start rowing, and if one boat manages to touch the boat in front ("bumping"), both crews pull over to the side, and the next day they switch places in the starting line up. It's not uncommon to see two boats trade places repeatedly -- this could happen because crew A has a much stronger start than crew B, but that crew B have much more stamina than crew A, so A will always chase down B relatively quickly, but B will always manage to catch A over the course of a longer race.