To many New Yorkers, Sunday is meant for bottomless mimosas and loaded bagel platters. But a growing legion of lean-limbed folks aren’t stuffing themselves at brunch at the end of the weekend. Instead, they’re filling up their Tupperware containers for the week ahead.

They’re meal preppers, and they take healthy eating to the Type A extreme. They plot out every breakfast, lunch and dinner for the workweek ahead, cooking multiple meals in a big batch and precisely portioning them into plastic containers. While this kind of menu planning has long been popular among professional athletes, now health-obsessed office workers and students are joining the movement, thanks to readily available information and inspiration on social media — and the advice of health professionals.

“I recommend it all the time to my clients,” says Joy Bauer, a Westchester-based nutritionist and the author of “From Junk Food to Joy Food.”

“People who plan their meals and track what they eat are more successful than dieters who don’t … Research shows that home-cooked meals are healthier — they’re lower in calories, fat, refined carbs and sodium — than meals [cooked] outside the home.”

It’s worked for Sean Peters, 31, a doctoral candidate in electrical engineering at Columbia University who began meal prepping in 2013.

“I didn’t have clear goals when I started, but I did see that I began to lose body fat, and my training [at the gym] was better,” says the 5-foot-10, 180-pound Peters.

He now spends several hours every Sunday prepping five lunches and five dinners for the week ahead, photos of which he shares with the 40,000-plus people who follow his Instagram account @mybodymykitchen. The Harlem resident admits that eating the same thing every day can get repetitive, but he says he combats flavor fatigue by using plenty of spices — just like with the Caribbean food his mother cooked when he was growing up. And he’ll sometimes make a large batch of soup and freeze it in portions so that he has something to stave off the monotony.

“You can sub out a meal here and there to break things up,” says Peters, who microwaves his healthy lunches in between classes at Columbia.

Like Peters, fitness model Alyssa Bossio and her partner, Meir Schonbrun, both 23, say meal planning has helped them reach their fitness goals.

“The number on the scale isn’t that different from when I began [two years ago]. I started at 140 pounds and am now 130,” says Bossio, who is 5 feet 4 and aims to eat 2,000 calories each day. “But my body-fat percentage is lower, I have more muscle tone, and physically I look [very] different.”

Meal prepping has also helped make her a social-media star. The Flatiron couple’s @how2mealprep Instagram account now has 1.8 million followers. Schonbrun has quit his marketing job to focus on business opportunities, and the pair is at work on their own line of fitness guides and Tupperware-like containers.

And while wholesome fare can be pricey, Schonbrun says that meal prep is great for those on budgets.

“People think eating healthy is expensive, but this way it’s affordable!” he says. “We’ll pay $75 to $100 at the supermarket, and that’s all you are going to spend on eating for the week.”