In a road bicycle race, the peloton (from French, originally meaning 'platoon') is the main group or pack of riders. Riders in a group save energy by riding close (drafting or slipstreaming) to (particularly behind) other riders.

The reduction in drag is dramatic; riding in the middle of a well-developed group, drag can be reduced to as little as 5%–10%. Exploitation of this potential energy saving leads to complex cooperative and competitive interactions between riders and teams in race tactics. The term is also used to refer to the community of professional cyclists in general.

In motorsport, such a formation is generally called a pack.

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