For some young enthusiasts, that childhood hobby can turn into an intense, life-changing sport. It catapults them out of bed at 5 a.m. on a Saturday, sending an adrenaline rush into every pore of their body as they prepare for a 50-mile bike race or a ride up open mountain terrain high above San Jose before the rest of the Valley wakes up.

For these cyclists, the seat belt has been replaced with a helmet and the V-8 engine with two pedals, and the road is the gateway away from life's daily stresses.

Although many seasoned cyclists know South Bay bike trails like the back of their hand, even the most skilled bike riders say they want to be pushed to stay fresh and challenged.

To push their competitive edge, some residents have become members of the San Jose Bicycle Club, a nonprofit group founded in 1939. It's a club that provides a connection between cyclists, allowing them to share their skills and passion with other like-minded riders.

San Jose Bicycle Club member and Willow Glen resident Craig Baker says he stumbled onto his obsession for cycling and the San Jose Bicycle Club seven years ago. Before his passion for riding took over, he was a professional bodybuilder. But while training he hurt his knee and was advised by a doctor to ride a stationary cycle as a form of rehabilitation. Soon after his knee was mended, he didn't want to stop riding, so he bought a bike and began training.

"I'm an engineer, so the whole bike-building process, like the mechanical aspects, really intrigued me," he says.

But his devotion to the sport is also personal. "My dad had a heart attack, and my uncle died of a heart attack," he says. "Besides the health aspect, it is also a great stress reliever for me."

Throughout the year, club members gather on Saturdays at 9 a.m. at the PW Plaza on Almaden Expressway for a 30-mile group ride. They will also gather after work to ride into the wee hours of the night.

One of Baker's favorite riding destinations is in the mountains above Los Gatos.

He spends four or five days a week, clocking nearly 20 hours, pushing his physical limits on roads, paths and trails all over the South Bay. In fact, it was his penchant for pushing the limit that fueled the receipt of a $182 ticket, after a ranger caught him mountain biking after dark in the mountains above Highway 9. He laughs off the ticket because despite taking these chances, the reward for such an arduous ride up the mountains was looking down on the nighttime lights of San Jose.

"That view is just the best," he says. "Once you buy a bike and get into it, pretty soon you fall in love with it, and then you get obsessed with it."

For 41-year-old Baker, riding 100 miles from his home to the ocean coast and back again is an ideal way to spend a Saturday. He has no qualms about dropping $3,000 on a mountain bike, because "I get value out of it and I look at it the way someone likes to buy a nice car."

He counts the club's Winter Series as one of his favorite racing seasons during the year. The series has 11 events, including time trials, a hill climb, criteriums—short, quick circular races—and three road rides.

"The Winter Series is like the world championship, except that it counts for nothing," he says. "I like the interteam rivalries. It's just so much fun to compete with my buddies."

These races, even the competitive ones that take place throughout the country, are about more than the money or prizes, Baker says. It's about pushing body limitations, earning bragging rights and putting personal pride on the line.

Baker's clubmate Jonathon Racine also looks forward to the Winter Series each year, and like Baker, he happened upon bike riding and racing after succumbing to an injury, his from running.

His doctor said he could either swim or cycle to rehab his injury, and he chose the latter. And after he jumped on the bike, he says he hasn't looked back.

"You get a lot of time to think about stuff," he says, describing the perks of his bicycle-riding hobby. "You think about what you want to do with your life. And when you're riding with a group of guys, you can talk out problems out loud; it's a way I've resolved some tough situations."

Racine, a web designer, says that the group's training rides are an important time to prepare for weekend races. The night before any given race he doesn't sleep too well, because he gets so excited. The moment he awakes, he has "butterflies" as he eats oatmeal and gulps performance drinks to prepare for the day.

"Five minutes before the race, you're in the spandex, going over the course, waiting for the race director to start the race," he says. "At this point, I get nervous—if you don't get nervous, you lose the fun behind it."

Although Racine doesn't usually finish in first place, he says the race toward the finish line isn't about proving anything, but about "team glory."

While racing, he wears a heart monitor and tries to compete toward beating his best personal time. The Willow Glen resident says the only downside to racing is the high costs that can quickly add up. He spends about $500 a year on his sport, which includes sport drinks, spare tubes and clothing.

One particular race he looks forward to is sponsored by the San Jose Bicycle Club, the Mt. Hamilton Classic. According to Racine, every cyclist club in Northern California is required to put on an event.

The course for this race climbs 4,500 feet in 20 miles to the top of Mt. Hamilton, then continues 43 more miles through remote ranch lands to the finish line in Livermore. The total elevation gain exceeds 6,000 feet by the end of the race. Because of the race's grueling nature, riders are told to carry a spare tire, a pump and all the water that can be stored.

Racine says about 350 racers, including professional athletes, attend the event from all over the United States.

"It's fun to be able to watch those guys up close," Racine says, referring to the professional athletes. "It blows your mind to see them race. This is our chance to see them in action."

Howard Zolla is a club member and one of the organizers of the Mt. Hamilton Classic.

Although he is very involved in the club now, it was only two years ago that he got back on his bike. He was inspired to take his bicycle out of the garage after watching Lance Armstrong dominate the field in the Tour de France bike race.

"It hurt real bad at first," says Zolla, a Willow Glen resident. "But after two months of riding, I joined the club and now ride on weekends and about three days a week."

Zolla, an engineer, competes in about 20 races per year, although he admits this year has been a little different, with a baby on the way. At 36 years old, he says there is a limit to how good he can become because of his age and other personal commitments in his life, but he just enjoys the sport, the races and the benefits it has for his daily life, such as relieving stress.

Like Racine and Baker, Zolla says that the many people he associates with outside of the sport don't understand the sport's time commitment, which includes early mornings and late evenings spent riding in the mountains or preparing for a race. But Zolla says other people's questioning doesn't impede on a cyclist's desire to keep digging a little deeper within to ride a little faster or a little longer or to beat a previous time.

Zolla describes a particular standout race last year. It was a 50-mile ride in 100-degree weather, yet he kept pace with the race leaders for much of the event, until he finally dropped back about 10 miles from the finish. Although he was devastated to fall back from the winning break—the lead group of racers—he felt a deep level of accomplishment after it ended. And, for him, that is what it is all about.

Club member Sean McLaughlin says he can relate to that feeling of accomplishment after a race.

Unlike Zolla, Racine and Baker, McLaughlin has been riding a bike almost his entire life and even combined his interest for cycling with his profession, working in marketing at Specialized Bicycles, a company that designs, manufactures and sells bicycles in Morgan Hill. Between working at the business and riding on his own, he spends between 10 and 60 hours a week in bicycle-related activities.

"I work in the business, and it's also my hobby," says McLaughlin, who lives in Willow Glen. "It is a lifestyle for me."

He joined the San Jose Bicycle Club four years ago because the club organizes a variety of different rides and "friendly" competitive events.

The 150-member club has a wide range of people, from teenagers to adults in their late 60s. Some are beginners, while others cycle competitively. Members pay a yearly fee, which allows them to participate in club racing, as well as in United States Cycling Federation competitions.

The United States Cycling Federation is the organization that selects the U.S. Olympic cycling team and through which members achieve professional status. Although all San Jose Bicycle Club members are amateur riders, the club grants its members coaching and organized racing-event experience aimed at increasing their skill, ability and enjoyment.

"Cycling seems to attract a diverse group of people," McLaughlin says. "There is a sense of motion and freedom that many of us find freeing."

He says it is one of a limited number of sports that people revisit as adults after learning to ride as youths.

"Many of us just seem to come back to it," he says. "We are rediscovering that joy we felt riding our bikes as a kid. I'm reminded of how much I love to ride almost every time. I just have a genuine love for the sport."

For more information about the San Jose Bicycle Club, visit http://www.teamsanjose.org or email mail@teamsanjose.org.