Do Jennifer Aniston’s compression leggings work?

No drain, no gain, according to Jennifer Aniston.

Aniston, 54, recently shared Instagram images of her post-workout regimen featuring some bizarre pants that look like a NASA laboratory creation.

It turns out Aniston was rocking Body Ballancer compression pants, designed to reduce swelling by using pressure to drain fluid from the lymphatic system (part of the immune system).

These and other types of compression leggings have been around for a few years and promise to control cellulite, support weight loss, improve digestion and boost the functioning of the immune system.

That’s a lot to promise. But do these compression leggings, which run from $10,650 up to $18,800, actually work or are they just another pricey Hollywood gimmick?

First, a bit about lymphatic drainage massage: It also has been around for years and is a medical technique used to relieve painful swelling in arms and legs caused when bodily tissues retain a clear, watery fluid called lymph.

Lymph is filtered by the lymph nodes located in the armpits, groin, neck and other areas, according to the Cleveland Clinic.

Some doctors recommend lymphatic drainage massage to people recovering from breast cancer surgery or who have rheumatoid arthritis, fibromyalgia or other conditions that cause pain and swelling.

And it’s possible that lymphatic drainage massage might benefit some people: A 2021 study reported that “there is some evidence that … in early stages following breast cancer surgery [lymphatic drainage massage] may help.”

However, most clinical studies have found little or no evidence that the technique can enhance the overall functioning of the lymphatic system or relieve the pain from lymphatic swelling.

For physical recovery after exercise, some athletes use compression garments like leggings or arm sleeves, but even for them, there isn’t a lot of evidence supporting their effectiveness.

A 2017 meta-analysis in Sports Medicine examined 23 studies into compression garments and concluded that “[t]he benefits of compression garments in relation to applied pressures and participant training status are unclear and limited by the paucity of reported data.”

So much for science: What do everyday users say about compression leggings? Despite the lack of evidence supporting their use, there are some rave reviews online.

“This lazy-girl-approved activewear trend is basically a dream come true,” said Mia Maguire in The Daily Beast.

“In my opinion, everyone who is active, travels a lot, and or is on their feet or sitting all day [which basically describes everyone] should wear them,” physical therapist Chad Beauchamp told Byrdie.

“Stagnation (aka sitting at your work desk for hours at a time) causes the lymphatic system to not work efficiently and fluid can be retained in the lower extremities. Compression pants can help aid in draining,” Beauchamp added.

The Body Ballancer might be called an extreme type of compression garment: It’s a zip-up suit that covers the lower body, or a jacket for the upper body.

The garments are attached through thick cables to an electronic device that pumps air into the garment, making them press against the body. “The bodysuit was like getting a very strong hug,” one user told Good Morning America.

The suits, developed in the UK in 2018, are now primarily found in spas and esthetic salons. NYC facialist Teresa Tarmey previously offered Ballancer Pro treatments for $250 a pop at her practice, as seen in a 2018 “Good Morning America” video, but it’s unclear if it’s still available.

But as far as reducing cellulite, flushing out toxins, helping with weight loss and sleep disorders, improving digestion or enhancing immunity, there isn’t any real-world evidence to support those extravagant claims.

A search for “Body Ballancer” on PubMed — an online repository for medical research — yielded zero results, and the company’s website offers no medical evidence to back up its claims.

When asked for more information, a Body Ballancer representative told The Post: “I’m afraid to say there are no scientific studies that have been carried out into the aesthetic benefits of the Body Ballancer.”

Even Hollywood health experts cast doubt on the overblown benefits of lymphatic drainage.

“If you have a healthy lymphatic system, lymphatic drainage massage isn’t likely to benefit you beyond simple relaxation,” stated a report from Cedars-Sinai, a medical research center based in Los Angeles.

“And despite celebrities claiming that lymphatic drainage massage makes them ‘red-carpet ready,’ there’s no evidence that lymphatic drainage massage can help you slim down,” the report added.

“Instead, using lymphatic drainage techniques may have a temporary trimming effect because it helps move fluid through the body.”