Stopping is not an option.
James Parry sprints 400 meters beneath the Mesa sun before plunging into 10 pull-ups. He breaks for a second to suck in some air and jolts back to the pavement. He keeps at it for 20 minutes.
The 27-year-old Gilbert man considers himself lucky for not vomiting when he collapses to the floor after his last, strained pull-up. But he loves every minute of it.
"You just kind of black out," he said. "You got to be kind of crazy to do this."
Thousands of fitness diehards like Parry are fueling a mass movement to increase strength and slim down around the country. The trend, called CrossFit, uses a surging 20 minutes of lifting, running, climbing or rowing to shock the exerciser's body into fast fat loss and strength gain. Focusing heavily on competition, CrossFit trainers challenge clients to beat their previous scores and beat each other's records.
Parry trains at the newest CrossFit gym in Mesa. Courtney and Mike Naujokaitis opened CrossFit SanTan near Phoenix-Mesa Gateway Airport. Nestled in an expanse of desert with the Santan Mountains in the distance, the gym started in March and has about 35 members recruited mainly by word of mouth. The 3,500-square-foot gym is stocked with a pull-up station that supports 12 people at once, enormous tires to flip with raw strength, rowing machines and climbing ropes.
The idea is to get fast results and spend little time in the gym compared with one- to two-hour stints in traditional fitness programs. Parry says he lost 5 percent of his body fat in one month. Stacey Sutherland, a 26-year-old CrossFit convert from San Tan Valley, ran 2 miles in 40 minutes in March and recently ran the same distance in 28.
But those within the field acknowledge serious health risks that accompany intense workouts. The CrossFit website cautions against a disorder called rhabdomyolysis, in which too much exhaustion breaks down muscles, excreting toxins throughout the body.
Light-headedness and vomiting are also common post-workout occurrences. Frequent discussion-board posts on the headquarters website boast of "meeting pukie," meaning that they worked out so hard they threw up.
Naujokaitis said he and his wife watch for overexertion, but newcomers often can't help but vomit.
"It's nothing to be ashamed of," Naujokaitis said. "We show them where the bathrooms are, where the trash cans are, where the desert is."
After 20 minutes, those left standing argue that the place is more than just a gym.