What's Up With Cupping? 6 Facts About The Ancient Recovery Method Powering Olympians Like Michael Phelps

Cupping is making a big splash at the 2016 Summer Olympics. Learn more about this ancient recovery technique.

What's wrong with Michael Phelps?

Sure, the guy's already added three gold medals at the 2016 Summer Olympics to make himself the most decorated Olympian of all time. But what about those dark purple bruises that have been omnipresent on his shoulders and back?

Why does the greatest Olympian of all time look like he's been standing in front of a pitching machine à la Happy Gilmore?

The answer is cupping, a recovery method that has caught on big with many Olympians (especially swimmers) at this year's Summer Games. Here are five facts about this eye-catching recovery technique.

1. Cupping Uses Specialized Suction Cups

Cupping involves placing specialized cups on the skin. Once the cups are on the skin, a heat or air pump is used to created suction and pull the skin underneath the cup up and away from the underlying muscles. The suction typically lasts only a few minutes.

Why is cupping potentially beneficial for athletes? Because the suction ruptures the blood-bearing capillaries just beneath the surface of the skin. According to the Cleveland Clinic, this promotes increased blood flow in the area. Increased blood flow helps the body more efficiently get rid of waste products and old blood and bring in fresh, oxygen-rich blood. The  body uses oxygen and nutrients from the blood to function, and it does this at a higher rate when we exercise intensely. When our cells can't get enough oxygen to keep up with strenuous activity, performance suffers and excess lactic acid builds up. For those who believe in the power of cupping, the technique is thought to help flush out the deoxygenated blood, lactic acid and other waste products from the extremities so that oxygenated, nutrient-rich blood can flow back in more effectively.

There are a variety of cupping techniques in practice, but they all rest on the central tenet of creating suction powerful enough to pull the skin away from the muscles and enhance blood flow.

2. Cupping Has Been Around for Thousands of Years

The earliest record of cupping is from the Han dynasty of China, which lasted from 206 BC to 220 AD. So yeah, cupping isn't exactly new. According to the Academy of Classical Oriental Sciences, cupping was often performed with cattle horns or cross sections of bamboo in ancient China. To create the necessary suction, fire was strategically ignited to expel the air from inside such items. Cupping is still extremely prevalent in modern China, used to treat everything from arthritis to asthma to the common cold.

RELATED: The Painful Recovery Method Pro Athletes Like James Harrison, Elena Delle Donna And Anthony Davis Use

3. Despite its Bruising Effects, Cupping Isn't Particularly Painful

A recovery method that leaves your body spotted with bruises doesn't sound like much fun. But just how badly does cupping actually hurt?

Despite the fact that cupping can look rather alien, many cite it as a relaxing or relieving sensation. However, if the cupping is performed on a sore area, you can expect to feel some mild pain—just as you would during traditional massage techniques. The cupping marks usually fade after a few days.

4. The Research on Cupping is Still Iffy

A 2010 review of 550 cupping-related clinical studies published in the journal BMC Complementary and Alternative Medicine sought to evaluate the therapeutic effect of cupping therapy. According to researchers, the "majority of studies show potential benefit on pain conditions, herpes zoster and other diseases. However, further rigorous designed trials in relevant conditions are warranted to support their use in practice."

It's not exactly a slam dunk, but there's reason to believe cupping could have benefits for certain athletes.

From an anecdotal standpoint, many athletes swear by cupping. "[Cupping] has been the secret that I have had through this year that keeps me healthy," U.S. Olympic gymnast Alex Naddour told USA Today. "It's the best thing that I've ever had. It has saved me from a lot of pain."

It's possible that the technique also provides a placebo effect. If athletes use it on a regular basis and find success with it, it's likely to stay in their routine. "There is a psychological component where Michael has been doing this to feel good for a long time, about two years," Keenan Robinson, Phelps's personal trainer, told the New York Times. "We know that science says it does in some cases help out. So we're at least going to expose the athletes to it years out so they can at least get a routine into it."

 RELATED: The Science Behind LeBron's Post-Game Recovery (And How You Can Use It)

5. Some of Your Favorite Athletes Probably Use Cupping

Other high-profile athletes who've used cupping as part of their recovery routines in recent years include:

6. There's Some Debate About The Safety of Cupping

There's some debate in the medical world on whether the potential benefits of cupping outweigh its potential harms.

The Cleveland Clinic recently published an article stating that cupping can be a "good addition to [an athlete's] general sports medicine routine" as long as it's administered by an expert such as a state-licensed acupuncturist. On the other hand, Steven Salzberg, professor of Biomedical Engineering at Johns Hopkins University, recently penned a piece for Forbes that claims cupping's dangers outweigh its benefits. "I'm not sure who told Michael Phelps that cupping would help him swim faster, but I am sure that it's terrible advice–definitely not helpful and maybe harmful," Salzberg wrote.

Meanwhile, techniques such as foam rolling and active recovery are widely agreed to be safe, effective ways of speeding up recovery via improved blood flow.

RELATED: How to Get The Most out of Foam Rolling

Photo Credit: Getty Images // Thinkstock