On a Monday evening in early November, the singer J’Nai Bridges, 32, is standing at the piano in the front room of her Harlem apartment. In just four days, she will make her debut at the Metropolitan Opera in New York, where she will sing the part of Nefertiti in Philip Glass’s 1983 opera “Akhnaten,” but tonight she is practicing runs from the 19th-century French opera “Samson and Delilah,” which she will perform at the Washington National Opera in the spring. Opera singers perform unamplified, and their voices must be strong enough to project to every seat in a cavernous auditorium like the Met. So when Bridges begins to sing in the small space, the sound of her mezzo-soprano voice seems to shake the walls. Often, when she’s practicing, passers-by on the street will stop and listen. “I wasn’t able to do that in undergrad,” she says of her resonance. “It’s just a lot of years of training your muscles.” She read that Beyoncé used to jog on a treadmill and sing in order to improve her live performance, so now, she says, “Sometimes I literally run around the room.”

Bridges, who has had a year of professional triumphs, including singing the title role in “Carmen” at the San Francisco Opera and performing for Justice Ruth Bader Ginsburg at the Kennedy Center, has an athletic approach to music that is deeply ingrained. As a high school student in Lakewood, Wash., she ran track and played basketball at the state championship level. She might have gone on to a professional career in basketball, in fact, had she not found opera during her senior year as a chorus member in Puccini’s “Tosca.” When a rehearsal fell on the same day as a finals game, her basketball coach made it clear she had to choose between the two activities. She never played competitive basketball again. Still, she says, “I’m thankful for my athletic background. It wasn’t such a shocker that I had to practice all the time.”