Thou shalt pound treadmills, pump iron, and worship the gods Ab, Pec, and Quad. Thou shalt submit to the caliper and the scale. Thou shalt throw out the junk food and bow down to the Salad. Thou shalt be thin, thou shalt be defined, and thou shalt be fabulous. Thou shalt also probably be “hetero-flexible.” Thou shalt not be hung up.

All this I have gleaned from the first two episodes of the third season of “Work Out,” whose third episode airs tonight on Bravo. “Work Out,” it should be stated at the outset, is the kind of “reality” television guaranteed to make a lot of fine, upstanding, sensitive, intelligent, thoughtful, and emotionally stable people gag, groan, or even take to their beds with a 19th-century novel written with a pen. It is not the sort of reality series on which people get voted off an island, cast out of their hotel suites in disgrace, or forced to endure the withering scrutiny of judges and juries, but it is about personal trainers. And not just any old personal trainers: This particular group of fitness instructors hails from Beverly Hills, Calif., the plastic heart of a surgical universe that is equipped with 100% organic palm trees.

In many ways, it’s hard to take “Work Out” seriously. One could, however, take it at face value, since the show is at least partly about happiness, well-being, fulfillment, and how to find it — a knotty problem on which hangs a good chunk of our service economy and culture. Approaches to the problem are myriad: A psychiatrist would listen to you for an hour and then hand you a prescription. A priest would urge you to trust in God and renounce your sins. A Zen Buddhist would make you, I don’t know, stare at the wall or something.

Jackie Warner, the loudmouthed, bleached-blond, lesbian queen-bee personal trainer who is the focal point of “Work Out” and the owner of the Sky Sport and Spa (the self-anointed “most exclusive gym in L.A.”), takes a strictly biomechanical approach. She and her cohorts tell their clients they can find happiness if they allow themselves to be whipped into shape. Being out of shape, or overweight, is more or less openly equated with being unhappy. The idea that it is possible to be fat and happy is not one the show entertains, although there are certainly people in the world who are both. I suspect Ms. Warner would admit the truth of that: You can be fat and happy. I doubt, however, that she would concede that fat happy people wouldn’t be even happier if they were toned, tan, and thin instead.

As it happens, there are a lot of people on “Work Out” this season who are seriously overweight, and Ms. Warner plans to save them. It’s a risky strategy for the show, because no one watches it to look at plump bellies — it’s more about lesbian kisses, shifting sexual identities, the endless quest for the perfect romantic partner, and bitching about one another in trendy bars.

On the other hand, the sight of all those corpulent unfortunates serves to highlight the physical superiority of the trainers, as well as Ms. Warner’s compassionate mission. She’s not just making hard bodies look more so; she’s taking on genuinely daunting cases — men and women who are “clinically obese” and need to lose as many as 50 or 100 pounds. (She’s the Mother Theresa of trainers!) To ensure she does the job correctly, she even enlists a doctor to provide her with a full medical analysis of her most difficult clients, and goes to great lengths to pair all with the trainer most likely to click with them.

It’s early days yet, but her new clients are grateful, even tearfully so. However, don’t expect the miraculous transformations seen in late-night infomercials. “Work Out,” as befits its title, is all about struggle, and some of Ms. Warner’s new charges will probably turn out to be uncooperative. And why not? After all, several of the trainers at Sky Sport are constantly at war with Ms. Warner themselves.

In a way, “Work Out” subverts the very idea it’s supposed to promote. Being healthy and looking good are all very well, but then what? Even allowing for the constant stream of conflict and jealousy and backbiting and power trips and interpersonal drama on which a show like this thrives (and which it skillfully supplies), it still raises the question of what exactly you’re supposed to do once you’ve got the six-pack and the perfect body-fat ratio and can proudly hit the beach in a thong.

One could argue that, even if they are unusually fit, the trainers on “Work Out” are only marginally happier than the general run of humanity. Ms. Warner confuses personal growth and maturity with insensitivity and bossiness. The prettiest female trainer on staff, Ms. Warner’s ex-girlfriend, Rebecca, is jealous about Ms. Warner’s new girlfriend, Briana, who’s jealous herself because Ms. Warner decided to take the gym’s female trainers on a lesbian cruise; Brian, who’s on the outs with Ms. Warner, is threatened by her hunky new hire, Greg.

What the trainers do have is a privileged position in the sexual marketplace. None would have trouble finding someone to sleep with, which may be the truest ideal of happiness the show ultimately promotes. Even if you hate your boss and half of your co-workers, so long as you’re sexually desirable, and can help others attain the same state, you can feel virtuous while indulging your carnal proclivities to the max. And you can be on TV. As far as “Work Out” is concerned, that’s about as good as it gets.

bbernhard@nysun.com