Ariel Gladney's favorite therapy for recovering from horseback riding leaves her with large purple welts. 

Cupping sessions — suctioning glass globes to the back, arms and legs — relieve her sore muscles and joints, 26-year-old Gladney says.

"I end up looking like I've been attacked by an octopus, but it's totally worth it," Gladney says. 

Many Americans first learned of cupping last week when swimmer Michael Phelps and other competitors appeared at the Olympics in Rio with circular purple marks on their backs and biceps. News stories quickly explained that the athletes used cupping to recover from tough workouts.

Cupping therapy dates back to at least 1550 B.C., when Egyptian texts mention the practice. Traditional Chinese medicine said cupping opened up the channels of the body's life force. Most modern practitioners tout its ability to manipulate the body's muscles and tissues like massage therapy.

"It’s kind of like taking a shrink-wrap off your body," says Rebecca Brumfield, who practices cupping at the Vida Pura Salon in Baton Rouge. "It loosens up all the adhesions and scar tissue underneath."

Since the Olympics began, several articles have questioned cupping's benefits. Hundreds of studies have tested the ancient practice, with some finding it helped various health issues from acne to facial paralysis, while others found it had just a psychological effect.

But a review of that research in 2015 found that "a firm conclusion could not be drawn" because the original studies were of "low quality," according to the Journal of Traditional Chinese Medical Sciences. 

One reason studies of cupping aren't well received, according to a Mayo Clinic article, is that researchers can't design a placebo — a fake version of it like a sugar pill.  

Athletes who seek cupping believe the effect is more than psychological. 

Gladney says cupping has helped soothe the back spasms she developed from falls in competitive horseback riding and years of wear and tear from her hobby. 

"It’s definitely helped me," she says. "I’m sure massage doesn’t help everybody, chiropractors don’t help everybody, and I’m sure cupping doesn’t help everybody."

Gladney compares cupping's effect to a deep-tissue massage. Gymnastics coach Joshua Roberts, 29, agrees, but he says deep-tissue massages hurt for days afterward and cupping doesn't. 

“You have more time to recover," Roberts says. "With a deep-tissue massage you need a couple of days to recover.”

Roberts was skeptical of the treatment at first. While he still favors massages over cupping, he sees how cupping can help by relaxing muscles that usually remain under tension. 

"I definitely think it helps," he says. "There are a lot of things that can’t be proven."

One of a handful of Baton Rouge-area practitioners, Brumfield has performed cupping at her spa since 2011. While in massage therapy training she read about traditional Chinese fire cupping, in which a flame is placed inside the glass globe to create a vacuum. The fire is removed, then the globe is placed on the body. 

She learned more about cupping while living in Mexico. In Baton Rouge, she was taught by a local acupuncture specialist and sought additional training. Now she performs fire cupping as well as more modern methods, which create suction without a flame. 

"It’s not a hoax or a fad," Brumfield says. "It’s not newfangled as a newscaster said about it."

Brumfield never mentions anything about the body's "life force" when she discusses cupping. She says it works by less spiritual means.

"It increases the circulation of blood flow to the tissue," she says, "which speeds up the healing process."

The marks aren't bruises, as many people are calling them, according to Brumfield. They're hickeys.

"Hickeys don't hurt," she says. "They are just burst capillaries."

Follow Kyle Peveto on Twitter, @kylepeveto.