As waistlines across the nation have ballooned, the commitment to lose weight has become the most universal New Year’s resolution.

In fact, the president of Weight Watchers North America, David Burwick, told National Public Radio that the first week of January is the biggest of the year for the company.

“This is our Super Bowl,” he said.

Meanwhile, La Plata County health clubs are trying to harness that enthusiasm.

Don Roberts, owner of Fitness Solutions 24/7, said his enrollment picks up 10 to 20 percent in the winter.

“I definitely see new faces around,” Roberts said. “We try to educate and motivate with free clinics and fitness challenges.”

Kim Oliger, owner of Core Value Fitness Center, said her classes are full.

“Our personal trainers and our classes have no more spots,” Oliger said. “Our five-month Train to Beat the Train class is full. There was a big jump in membership from December to January.”

Train to Beat the Train refers to getting in shape for the Iron Horse Bicycle Classic, which pits bicycle riders against a Durango & Silverton Narrow Gauge Railroad locomotive over the 50 miles between the cities.

Nick Becker, owner and manager of Anytime Fitness, saw people with New Year’s resolutions start coming in the door starting in December.

“I’ve had 40 new enrollments since Dec. 1, with 15 of them since Jan. 1,” Becker said. “A lot of people are pledging to lose weight.”

The Durango Sports Club has scheduled six sessions of Work It in the Circuit that will start Jan. 16 to help people get fit in the new year. Circuit training is held at other times, too.

Participants visit about 20 stations, working out intensely for one minute at each.

The routine, which takes about 45 minutes, alternates among aerobic exercises and calesthenics-style movements with a body bar.

Teams of two participants will vie for prizes, based on the total number of inches lost in the six-week program.

Circuit training isn’t new, William McGarva, club general manager and personal trainer, said Thursday while leading a workout.

Miranda Framer, 55, a veteran circuit participant, wasn’t huffing and puffing.

“I’ve been doing this for a year,” Framer said as she moved between stations.

Julia Dodd, 65, is an inveterate exercise buff.

“I was a personal trainer when I first came to Durango,” Dodd said. “Now I work out five to six days a week.”

Dodd and Framer are sold on exercise, but many Americans aren’t. Almost one-third of the population is obese.

Obesity is a score of 30 or more on the body-mass index scale, which is a ratio of weight to height. A BMI score is calculated by multiplying one’s weight in pounds by 703 and dividing by height in inches squared.

Becker at Anytime Fitness is experimenting with psychological motivation. He has hung a clothesline in the gym to which members are attaching items that represent their reason for losing weight or, in a couple of cases, bulking up.

The attachments include a Speedo, a pair of hot pants, a swimsuit and photos of a wedding dress, grandchildren and Engineer Mountain.

An XL T-shirt is the motivation for a guy who wants to put on some weight.

“These are visual reminders of why they exercise,” Becker said. “One person is training for the Iron Horse and another is preparing for the Tough Mudder competition.”

The Tough Mudder is a 10- to 12-mile obstacle course held in a number of places annually.

Whether the weight-loss fervor carries into coming months remains to be seen.

Losing weight was the No. 1 resolution of 27 percent of 738 respondents to an online poll by The Durango Herald. Saving money was the top goal of 14 percent, and 7 percent pledged to quit a bad habit.

But 42 percent said they had made no resolutions.

daler@durangoherald.com