They’re yelling instructions to the sweepers so the stone ends up in exactly the right spot.

What are they actually shouting?

Some of the most common calls you hear in English are:

  • “Hurry!” / “Hard!” / “Hurry hard!” – Sweep as fast and as strongly as you can, often with lots of downward pressure.
  • “Clean!” – Light brushing with almost no pressure, just to clear debris so the rock keeps gliding.
  • “Whoa!” / “Off!” – Stop sweeping right now so the stone slows down or curls more.
  • “Line!” / “Curl!” – Adjust sweeping to keep the stone straighter (“line”) or let it curl more (“curl”).

Different countries and teams have their own slang, but it all boils down to: sweep harder, sweep softer, stop, or adjust the line.

Why is everyone screaming?

Curling ice (a “sheet”) is up to about 150 feet long, and the skip (the player calling the shot) is usually at the opposite end from the sweepers.

  • The arena is noisy: crowd, other games, and the natural “roar” of the stones sliding on ice.
  • Yelling is simply the most reliable way to communicate quickly and clearly over that distance.
  • The repeated, louder shouts also signal urgency: the more intense the voice, the more desperately they want sweeping (or for it to stop).

Because players are often mic’d up for TV, you hear everything , so it sounds even more dramatic at home than it feels to the players.

Is there really strategy behind it?

Yes—every yell is about fine‑tuning a shot in real time.

  • The skip can see the whole house and how the shot is developing, while sweepers are focused on the rock.
  • As the stone slides, ice conditions, speed, and curl are constantly changing, so the skip updates instructions second by second.
  • A fraction of a second too much or too little sweeping can decide whether a rock is perfectly buried, wide open, or misses altogether.

One way to picture it: imagine a golf shot where the ball is rolling for several seconds and the caddie can still influence its path by brushing the grass in front of it—curling sweep calls are the caddie yelling live adjustments.

Mini “forum-style” take

“They’re not just randomly screaming; they’re basically live GPS for the rock: ‘Go faster, slow down, stay straight, now stop!’ Without all that yelling, top‑level curling would fall apart pretty fast.”

TL;DR:
They’re yelling things like “hurry hard,” “whoa,” and “clean” to tell the sweepers exactly how and when to sweep so the stone travels the right distance and path across a long, noisy sheet of ice.

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