Q. Is singing exercise? Could I lose weight by vocalizing?

A. Singing, especially the kind that involves the deep breathing of trained opera singers, certainly exercises the muscles directly involved in breathing. Small studies have indicated that such singing can have cardiovascular benefits, but weight loss is unlikely, and one study suggested that singing might predispose singers to weight gain.

A 1986 study in The American Journal of Nursing compared heart and lung function in 20 opera singers 28 to 65 years old with that of a control group of nonsingers, all under 40. It found that the opera singers had stronger chest-wall muscles and that their hearts pumped better. The singers also maintained a large lung capacity, something that usually declines with age.

A 2006 study of four singers focused on the action of the specific muscle groups and body zones involved in operatic singing over three semesters of training. The study measured lung volume and rib cage and abdominal expansion and found results suggesting that the respiratory system is highly responsive to vocal training over even a short period.

On the other hand, a 2005 study suggested that singers’ prolonged use of their lungs set off an increase in the hormone leptin, making the brain resistant to it. Leptin, made in fat cells, helps the body keep track of fat storage, and a resistance to it might lead to weight gain, the author suggested.

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