Along with the many dependable pleasures of late spring— outdoor drinking, not having to wear (or see anyone else in) bulky sweaters— comes one reliable moment of panic: Crud, it's almost bathing-suit season. 

If, after a winter spent hunched over your Seamless app, your chest isn't exactly ready for public consumption, you could commence the push-ups and the eschewing of bread and alcohol. Or, thanks to a new procedure called Instapecs, you could see a doctor, get a shot in each areola, then head (newly swollen) to the beach.

RELATED: The Only 5 Exercises You'll Ever Need

Instapecs are the invention of Dr. Norman Rowe, a plastic surgeon in New York City who discovered that quick and painless saline injections mimic real volume and definition in the pectoral muscles. If it sounds too good to be true, it is: They last just 24 hours. That hasn't turned off patients like Jared Luongo, 28, who got Instapecs last year after three days a week of dedicated bench-pressing failed to help him fill out his Uniqlo T-shirts. The results were intoxicating. Luongo said that, after the surgery, he felt more confident, and especially at the gym.

RELATED: How to Get a Ripped Chest, Fast

Luongo, a director of international strategy for a consumer- packaged-goods company, had heard about permanent pectoral implants from a guy at his gym. "Everyone has their trouble area," he explains. "And mine's my pecs." Apprehensive about going under the knife— he knew acquaintances who'd had botched procedures in South America— he ended up on Rowe's website, reading about Instapecs. He was intrigued enough to book an appointment. After Rowe squeezed about four ounces of fluid into each of Luongo's nipples ("It just felt like a pinch"), Luongo went home and stared at himself in the mirror for a solid hour. That night, he went to a club, where a friend commented that he looked unusually built. Luongo came clean; his friend is now looking into Instapecs himself.

RELATED: Ludacris Shares How He Keeps His Flawless Body In Check

Like most other cosmetic injections, Instapecs were developed for women. Rowe had noticed that his standard pre-boob-job injection of saline and a local anesthetic gave breasts a nice natural volume; unfortunately, it was absorbed by the body within a day. He decided to market that ephemerality as an asset. At $2,500, Instabreasts were an immediate sensation: a way to test-drive the results of surgery before committing to the risks— or, perhaps, a very expensive way to prepare for one's high-school reunion. Instapecs, which cost a relatively modest $800, were born soon after, when a male patient wanted in on the action. Rowe now also injects saline into calves, butts, cheeks— basically anywhere he can put an implant.

RELATED: Shirtless Nick Jonas Explains How He Got His New Body

The doctor insists they're completely safe, since "salt water is pretty much what our body is made up of anyway." But, he cautions, "Instapecs work best on a person who's got something to begin with. It's not like you can take someone with man boobs and turn him into the guy from Thor."

RELATED: Earlobe Reductions and Other Really Odd Plastic-Surgery Trends

Of course, not every doctor is convinced that injectable muscles represent an exciting new frontier. "Not only do you risk nerve damage; you risk lymphatic obstruction, which can cause painful swelling," says Dr. Dendy Engelman, a cosmetic dermatologist in New York. "All for something that's going to last hours, not years." (The risk, she explains, is not the saline but the volume required, which when inserted improperly can block channels that lead to the lymph nodes.)

RELATED: Brad Pitt Is Back and Sexier Than Ever

Rowe's semipermanent crusade, though, isn't stopping. He's currently working on "vacation pecs," which will last several weeks. In fact, he believes that in 5 to 10 years, all injectables will be permanent— and the kind of "heavage" Ryan Gosling has made famous with his endless parade of unbuttoned henleys will never be more than a doctor's visit away.

Click for more from Details.