Sweeping: Curling’s iconic skill is harder than it looks

EVERETT — If there’s one thing the uninitiated know about curling, it’s that curling is the sport with the broom. The greatest spectacle in curling is watching two players furiously sweeping in front of a moving stone as it slides down the ice, while the team’s skip hollers at them to sweep even harder.

But what is the sweeping all about? Why do teams sweep, and what does it accomplish? Participants in this week’s USA Curling National Championships at Xfinity Arena helped explain the secret behind sweeping, revealing that sweeping is part science, part art and a whole lot of sweat.

“It’s a lot harder than it looks,” said Becca Hamilton, one of the best sweepers in the U.S. women’s game and a member of Team Roth. “A lot of the curlers here are elite curlers and they make it look a lot easier. But I guarantee, it’s kind of an art you have to master.”

The basic concept behind sweeping is simple. When players sweep in front of the rock they are warming the path the rock takes, and the rock moves farther on warm ice than it does cold ice. Therefore, when players sweep in front of the rock, they are trying to extend the length it travels along the 150-foot ice sheet. Good sweeping can add as much as six-to-10 feet to the distance a rock travels.

But there’s more to it than just distance. When a thrower releases the rock, he or she also gives it rotation that causes the rock to turn, or curl. When players sweep, they not only cause the rock to go farther, they also cause the rock to curl less.

So finding that balance between affecting a rock’s distance and affecting its curl is the essence of sweeping.

“Sweeping is where all the depth in the game comes from,” said Colin Hufman, who serves as a primary sweeper for Lynnwood’s Brady Clark and is a defending men’s national champion. “If you look at basketball, it just looks like people trying to get by each other to get to the rim. But there’s a lot of really specific moves going on in their heads, like seeing the way the defender leans. Sweeping is where all the precision in this game comes from. The thrower just gets it close, the sweepers are the guys who put it exactly where it’s supposed to be.”

Who makes the decisions on whether or not to sweep, the sweepers of the skip? Well, that depends. The sweepers are traveling with the stone, so they have a better idea about how fast it’s moving. Meanwhile, the skip is squatting behind the house, looking down the length of the ice, and thus has a better read on the rock’s line.

Therefore, the sweepers and skip are constantly communicating back and forth as the rock slides — hence the yelling that curling is famous for.

“On all draws (when trying to place the rock in a specific position), it’s the sweeper first who’s making that decision,” said Matt Hamilton, a primary sweeper for Team Schuster, one of the men’s favorites. “He’s going to tell the skip how fast it’s going. When it’s a takeout (designed to knock rocks out of the house) and weight isn’t nearly as important, it’s more about the line and the skip has the first call.

“Typically you try and make split-second decisions, relaying what you know to the other guys so that you can make a fast decision of whether to sweep. So a good sweeper is a good communicator.”

A good sweeper is also big and strong. One thing many may not understand about sweeping is how much physical effort is required. In each end a sweeper could be called into action as many as six times, so in a 10-end game that could mean up to 60 reps. At its most vigorous a sweeper may have to exert maximum effort, both in terms of pressure being put on the broom and the speed of sweeping, for up to 30 seconds.

Therefore, sweepers who want to curl at the elite level must to be in top physical condition. Matt Hamilton is built like a football player, while Hufman has a physique that would be right at home on the basketball court.

“You have to like the idea of suffering to some degree because you have to be able to go as hard as you can,” said Hufman, who’s in the gym doing weight training or high-intensity interval work four to six times a week. “Even though it doesn’t look like the most athletic game in the world, you’re giving 100 percent. If a rock needs to get there, you have to go as hard as you can until it gets there. So you have to be able to dig deep, and when you’re tired and you can feel your arms starting to go, you have to keep going.”

The sweepers take a back seat to the skips when it comes to glory in curling. The skips are the ones the team is named after, and they’re the ones who throw the final two rocks of an end, thus having the most effect on scoring.

But while the skips get the spotlight, it’s the sweepers who do the grunt work. And whichever skips end up winning national titles this weekend at Xfinity Arena, they’ll owe a big debt of gratitude to their sweepers.

For more on the Seattle sports scene, check out Nick Patterson’s Seattle Sidelines blog at www.heraldnet.com/tag/seattle-sidelines, or follow him on Twitter at @NickHPatterson.