The fluorescent halls of Nathan Hale School were eerily empty on a cold Tuesday night.

But the gym was filled with music, footsteps and the relentless sound of flesh hitting rubber as a dozen adults sought athletic glory in a coed New Haven Volleyball League game.

The league’s founder, Oswald Hernandez Carrero, known by everyone as Ozzie, watched from the sidelines in an orange t-shirt and blue sweatpants, greeting players walking into the gym in English or Spanish. Tonight, the Notorious DIGs, a team composed mostly of faculty and staff affiliated with Career High School, were taking on the undefeated Vinotinto, named for the Venezuelan national soccer team. The players differed in age, national origin, fitness level and socioeconomic status.

“It’s amazing,” Carrero said, gesturing across the gym. “He’s an illegal immigrant playing with doctors, lawyers, police officers.”

Carrero grew up playing volleyball in Puerto Rico before attending Eli Whitney High School in Hamden. He founded the league three years ago with the sponsorship of the Department of Parks, Recreation and Trees. It now boasts 20 teams and over 135 players — most of whom live in the New Haven area. Each team pays $100 for the season, which lasts from November through April, creating one of the best volleyball bargains in the state, according to Carrero. Other recreational leagues in cities such as Wallingford, Woodbridge and West Haven, for example, charge teams at least $200 and as much as $500 for three months of play.

According to Felicia Shashinka, community recreation coordinator at the department, the league may also be among the most affordable tools in the city’s fight against obesity. A 2013 survey of adults in six New Haven neighborhoods, conducted by the Community Alliance for Research and Engagement, found that 70 percent reported being overweight or obese. A report published by DataHaven that year found that half of Elm City middle school students did not meet healthy weight guidelines, compared to one third of children between the ages of two and 19 nationwide. The volleyball league provides cheap and fun exercise, and the participation fee means “it’s a wash” for the city’s coffers, Shashinka said.

On Tuesday, a few players had brought their children to the gym to watch the games. They threw volleyballs at the wall and ran along the sidelines as their parents played. Shashinka said that’s a sign of the program’s multiple benefits.

“If you see your parent do it, your tendencies are better to start being fit and start exercising at a younger age,” Shashinka said.

The city provides the League with space, some equipment and an employee who observes the game and keeps score. The Department also helps advertise, publishing flyers and occasional updates about the league in its newsletter. The backbone of the program, however, is Carrero himself, according to many players interviewed.

Shashinka said he approached her three years ago with his plan for the League. West Haven runs a beach volleyball program in the summer, and Carrero wanted New Haven to offer an indoor league in the winter months. Shashinka told him to go for it.

During the League’s season, he is at Nathan Hale five days a week from 5:30 to 9:30 p.m after he leaves his job as a claims representative at the social security administration on Church Street. There are typically three games per day and about a half hour of open play.

In the fall, Carrero, who also plays on a team called the Volley Llamas, runs team registration and hosts a few days of open play, during which unaffiliated players have the chance to show off their skills. Teams in search of new members show up, sit on the sidelines and scout.

Volkan Gok, who works as a client advisor for BMW in Bridgeport, was recruited to join team Vinotinto more informally. One Sunday during the summer of 2013, he was on the way to a soccer game on his motorcycle when he passed a game of beach volleyball in West Haven. Gok played volleyball in college in Istanbul, so he stopped to see how the team was playing.

“They said, ‘Hey would you want to come next Sunday? We’re here every Sunday.’ So the following week I joined them,” Gok said.

In the fall, they invited him to join their indoor volleyball team. They are currently the strongest team in the league, and Gok, who does crossfit three or four times a week, is a major contributor to their success. For Gok and most other players, including Rosa Ayala ’09, a math teacher at Career High School, the competition is fun, but not the main point of playing.

Instead, Gok cited the sense of community that develops among players in the league as a main driver in his decision to play. Although teams are set, anyone can show up on any night and expect to play, since teams often need substitute players at the last minute. That means players have the chance to meet almost everyone in the League.

“Once you get out of your childhood, teen years, you don’t always find these things,” Gok said. “You have to find communities.”

Though the League is a particularly unique opportunity for adults, Carrero’s work has also spurred a new opportunity for New Haven high school students: the first-ever city-sponsored youth club team. The team started when Carrero’s niece, Kiana Hernandez ’18, started attending League games with fellow Wilbur Cross High School women’s volleyball players. Carrero encouraged her to enlist more players to form a team, and last year they began traveling to tournaments across the northeast. After a few tournaments, officials from the city’s Department of Parks, Recreation and Trees then decided to sponsor the team, so Carrero hired a former Albertus Magnus College coach, Omar Ramirez, to bring the New Haven Bulldogs up to par with club teams across the region. The Bulldogs are the first club team in the city traveling and representing New Haven across the northeast.

Hernandez, who still practices with the club team, said the players — who mostly come from Wilbur Cross but are looking to expand the number of schools involved — have improved significantly this year. Two of her cousins on the team hope to play well enough to join college teams.

Shashinka said hope represents part of the logic behind funding the club team.

“If the skills get set, there’s an opportunity for them to get scholarships and continue education,” Shashinka said.

Carrero said he recently had a conversation with Shashinka in which she explained why the city has been so supportive — in addition to paying the salary for the club coach, the city pays Carrero a salary of $10 an hour.

“Her thing is, ‘You work with the youth, you get the adults going, and you really don’t bother me,’” Carrero joked.

Carrero said he hopes the new club team can expand its reach beyond its own players. In the spring, the women will lead a volleyball clinic for elementary school students, passing along their passion to the next generation of players.

Hernandez said she thinks Carrero’s passion for volleyball started because of the sport’s popularity in Puerto Rico and within their family. Her parents and cousins play as well.

“It started off as a family affair and now he wants to spread his love to the city,” Hernandez said.