Sweepers in curling use their brooms to control how far and how straight the stone travels by reducing friction on the ice, judging its speed, and communicating with the skip to fine‑tune each shot.

Quick Scoop: What sweepers actually do

  • Make the stone go farther.
    Fast, vigorous sweeping slightly warms the ice in front of the stone, reducing friction so it keeps gliding instead of slowing down too soon.
  • Keep the stone straighter (less curl).
    Sweeping can reduce how much the stone “curls,” helping it stay on a straighter line toward the target when the team needs precision.
  • Clean the path.
    Bits of debris or frost can make a stone “pick” and jump off line; sweepers clear that away so the stone has a smooth, predictable track.
  • Judge the weight (speed and distance).
    Sweepers skate alongside the moving stone and are usually the best judges of whether it’s too heavy, too light, or just right for the called shot.

They call out what they feel—often in short codes—to help the skip decide whether to keep sweeping or back off.

  • Follow the skip’s strategy.
    The skip stands in the house and calls “Yes!” for more sweeping or “No!” to stop, trying to land the stone exactly where they want it for the team’s game plan.
  • Work in sync as a pair.
    On most shots, two sweepers work together: the one closest to the stone has the biggest effect on the ice right under it, while the second “pre‑warms” and helps with timing and communication.

A quick story‑style example

Imagine a draw shot that needs to just reach the front of the house.
The thrower lets the stone go, and immediately the two sweepers move with it, watching how fast it’s sliding. They feel it’s a little light, so when the skip yells “Yes!” they sweep hard in front of the stone, warming the ice and squeezing a few extra feet of distance out of it.

Because they judged the weight correctly and swept at the right moment, the stone dies exactly on the top of the rings instead of stopping short. TL;DR: Sweepers aren’t just “cleaning”; they are active shot controllers, using sweeping, judgment, and communication to fine‑tune the stone’s distance, line, and overall outcome on every shot.

Information gathered from public forums or data available on the internet and portrayed here.