When you arrive on location at Delta CrossFit, don’t let the outdoor pull-up bars, weight-lifting stations or aerobics equipment surprise you. Just walk on through toward the small office building and prepare to join a friendly fitness family of CrossFit enthusiasts.

Boasting 2,500 affiliates worldwide, CrossFit is an alternative “to the prevailing commercial gym establishment and its machine-based, bodybuilding approach to fitness,” according to the CrossFit website. CrossFit employs a strength and conditioning program that breaks the mold and promotes endurance, versatility and group workouts.

Hayward Fire Department firefighter Chris Castillo was introduced to the CrossFit phenomenon several years ago. Tired of workouts that didn’t improve his strength and stamina, he began exploring CrossFit at the urging of a friend.

“I tried to do what they were doing, and I couldn’t,” he said. “There were girls doing 60 pull-ups, and one was even pregnant at the time, and I thought, ‘Oh my gosh, I feel way out of shape.’ That was my motivation back then.”

Chris introduced his wife, Mayra, to the concept. She had recently given birth to her second child and was interested in switching up her workout routine. “You get quick results if you put in the effort,” she said. “You see yourself getting stronger, and for me, that was huge. In the past, I couldn’t pick up a 45 pound barbell.”

Through CrossFit, Mayra saw her strength increasing. “Along with that,” she said, “it’s just fun. Every day you do something different, so you don’t get bored with it.”

It didn’t take long before the couple convinced Sean Maloney to join. “Initially, when Chris told me about CrossFit, I blew him off,” said Maloney who also works for the Hayward Fire Department. “But I watched him lose 40 pounds, and his strength went through the roof. We started to keep in touch and share our workouts via phone.”

Eventually, the threesome opened a CrossFit affiliate in 2007.

CrossFit doesn’t categorize members into levels or use machines. It promotes the idea of becoming a generalist rather than a specialist, enabling you to perform a whole host of exercises well using weight options suited to your needs. Whether you’re an out-of-shape office worker or training for a SWAT team, CrossFit offers an intense, well-rounded workout designed to push you to your limit.

For example, “Karen” suggests you perform 150 “wall balls” – tossing a weighted medicine ball against a wall while doing squats. Other exercises include “double-unders” – spinning a jump rope twice before jumping. “Burpees” consist of lying on the ground, doing a push up, standing up and clapping your hands over your head and then rapidly repeating the sequence multiple times.

“We always say that we’re rehabbing the body back to what you were able to do when you were a child,” said Mayra. “The flexibility, the range of motion, the strength to move your body weight in, say, a cartwheel. As we age, we stop doing a lot of these movements, become inflexible and lose our strength.”

According to Jaymes Laughlin, local firefighter and Delta CrossFit coach since 2007, “Some people just want to change their status quo, but they have almost zero confidence in themselves and their abilities. One of the most humbling and rewarding experiences for a coach is watching that person transform in the span of an hour. That’s what I live for right there.”

Delta CrossFit originally started small, but has since morphed into a 120-member group with its own open-air gym site (indoor workout space is also available). Individual coaching and comradeship come standard with this crowd. “What we have is coercion through community,” Laughlin said. “We’re a tight-knit group, and there are no holes in that weave.”

Last Saturday morning, Delta CrossFit hosted CrossFit for Hope. Members not only enjoyed a killer workout, but raised $1,750 for St. Jude’s Children’s Research Hospital.

Stacey Phillips was one of the members participating in the event. It’s difficult to imagine the lean and muscular Phillips as non-athletic, but she joined Delta CrossFit only two years ago. “I started at 150 pounds and unable to do a sit up,” she said. “Now I can do just about everything.”

For more information about Delta CrossFit, 29 Spruce St. in Brentwood, visit www.deltacrossfit.typepad.com or call 925-783-6997.