GANGNEUNG, South Korea — Thomas Ulsrud lifts weights, hammers through squats and hangs upside down from metal bars, molding his abdominal muscles with a sadistic series of crunches. His torso has more ridges than a fjord.

“I guess I was blessed a little from nature’s side,” Ulsrud said, “but I do like to work out.”

None of this would be all that unusual except that Ulsrud is a 46-year-old curler.

Obliterating the sport’s tired reputation as ground zero for paunchy, beer-swilling weekend warriors, curlers like Ulsrud, who is back at the Olympics for the third time with Norway, are representative of a growing emphasis on fitness — for men and women alike. They bench press, bang out bicep curls and lay off the sauce.

Some, like Ulsrud and Marc Kennedy, a Canadian Olympian, have gone so far as to showcase their physiques in racy promotional calendars for the sport.