When people walk into the St. Paul Curling Club, Jim Dexter tells them to enjoy themselves. It's not a platitude. It's an order.

"If you can't have fun in this building, get out," he said.

Dexter joined the club in 1960 and was still curling until he ran into health problems four years ago. These days, he's listed as the club's assistant manager, where his primary duty appears to be making sure that people are having a good time.

It's not a tough assignment. Curlers pride themselves on their sociability.

"This is the only sport where, after you beat an opponent, you buy them a drink," said Nancee Melby, who has been curling for 10 years. "Don't get me wrong — we're very competitive. But after the game, we're friends."

The postgame camaraderie is such an established part of curling that the club's bar is set up with large, round tables, each surrounded by eight chairs. There are four people on a curling team; do the math.

"That interaction is what sets curling apart," said Tim Lindgren. "Sure, softball teams go out for a beer after a game, but each team goes to their own bar. We go upstairs and talk about the game with the team we just played."

That can be an unusual experience for people who are making the transition from less congenial sports.

"I started doing this after playing hockey, and it takes a while to learn that level of sportsmanship," said Dan Frey. "You're expected to congratulate your opponent for a good shot. That first year, we were out there getting our butts kicked, and it was tough. In hockey, if you're playing badly, you can get a little chippy and knock somebody down. But this isn't like that. You have to be very polite."

But it has paid off. "I've made friendships here that will last a lifetime," he said.

All in the family

For two weeks once every four years, the public rediscovers curling thanks to the Olympics.

But the sport doesn't disappear when the winter games end. On the contrary, it's booming. There are now 25 curling clubs in Minnesota, including four in the Twin Cities: the Four Seasons in Blaine, Frogtown in St. Paul, Dakota in Burnsville and the great-granddaddy of them all, the 101-year-old St. Paul Curling Club, which, with its 1,200 members, is the biggest in the country, said Dexter.

Curling has had its dry spots. In the 1920s, membership dropped to the point where the St. Paul club considered folding. Interest lagged again in the 1970s.

"We were down to about 250 members," Dexter said. "You could pretty much show up anytime you wanted and curl."

You can't do that these days. The club has leagues booked on all of its eight rinks seven evenings a week. There are daytime leagues, a youth league on Saturdays and tournaments (called bonspiels) just about every weekend. The club also has become a popular site for corporate outings.

Many of the curlers credit the Olympics for the surge in public interest. When curling became an official Olympic sport in 1998, "You could see the difference right away," Frey said. "Now you have millions of people watching it on TV and getting curious about it."

It's a lifetime sport, involving kids as young as 8 and seniors like Harry Byrnes, who, at 78, still participates in a weekly league.

"It gets in your blood," he said. "The tradition of sitting down with the opposing team — that social aspect — is at least 50 percent of it for me."

Having entire families involved is commonplace. There are parent-child teams, sibling teams, spouse teams and cousin teams.

"It's like incest," joked Judy Olsen, a third-generation curler.

Chris McGirl — who often bumps into her relatives on a curling rink — said those ties are what sustained the sport before TV audiences discovered it.

"That used to be how it kept going," she said. "Before the Olympics, this sport was pretty much unpublicized. The membership grew by recruiting friends and relations to come join."

New meets the old

The game's focus — getting your stones as close to the center target as possible while blocking your opponents' shots — is the same as when curling was developed in Scotland during the mid-1500s. But technology has changed the way it's played.

When the St. Paul Curling Club held its first match on Dec. 24, 1912, there were no refrigerated rinks. Members flooded the floor, then opened the doors and windows to let Mother Nature provide the ice. The resulting surface was bumpy and uneven, requiring the curlers to pick up the 42-pound stones and throw them in a motion similar to bowling.

The pristine ice in modern-day rinks has changed the emphasis from strength to finesse, Dexter said. Now curlers slide the stones using energy generated by their legs as they push off from what's called a hack, a foothold similar to the starting blocks used by runners in a 100-yard dash.

The brooms used to influence the speed and curve of the stones also have evolved. Wooden brushes with corn bristles have been replaced by high-tech brooms made of fiberglass or carbon fiber and outfitted with artificial heads that allow the sweeper to apply more pressure to the ice.

"The young curlers don't have a clue what it used to be like," said Byrnes, who started curling when he was in junior high. "Everything now is so predictable. The stone always goes where you throw it. It used to be a lot harder. The ice was so bad that a stone would just fly off on you."

He paused before adding: "Of course, the curlers also are better athletes now."

And they are athletes. Before the Olympics are over, someone — a blogger, a reader commenting on an online news story or maybe a self-acclaimed know-it-all in a bar — will opine that curling isn't a sport. The curlers beg to differ.

A curling rink is 150 feet long. By the time a player has run up and down it for eight "ends" — think "innings" — trying to keep ahead of the stones, they will have gone at least two miles, Melby said.

Add the stress of frantically pushing on a broom and it quickly becomes a workout, said Olsen, who wears a heart monitor during games. "It'll get up into the 170s [beats per minute] when I'm out on the ice," she said.

The Olympic curlers put a premium on fitness, said Dexter, who has coached world-class curlers.

"That's one of the first things we learned when we went to the Olympic training center," he said. "The Olympic athletes don't socialize after a game. They play longer games [10 ends instead of the recreational eight] and often play two games a day. And when they're not on the ice, they're in the gym."

Dexter interrupted himself to turn his attention to a person who was leaving the club.

"Be sure to come back," he beckoned. "I'll buy the first beer."

Jeff Strickler • 612-673-7392