Star American swimmer Michael Phelps earned the 19th gold medal of his career Sunday during the 100-metre freestyle relay — but while some were busy celebrating his accomplishment, others were fixated on the strange circular bruises covering his back and shoulders.
FULL COVERAGE: Rio 2016 Olympic games
“What the… Are those hickey marks on Michael Phelps,” asked one Twitter user.
“What’s up with all the hickeys, Michael Phelps,” said another.
But no, Phelps did not have a wild night out prior to his return to Olympic glory. Those deep purple bruises are the result of something called cupping therapy.
What is cupping?
Cupping is a traditional Chinese medicinal therapy that is being increasingly used by acupuncturists and physiotherapists to treat sore or aggravated muscles.
The therapy involves applying round suction cups to a patient’s skin, pulling the skin away from the underlying muscles. This allows blood vessels to expand and blood to flow more freely to the targeted area.
There are a few different forms of cupping. Some professionals use silicon cups that are tightened with an air pump, but more traditional techniques include heated glass cups that are set on fire to create a vacuum seal.
Phelps likely uses the therapy as part of his overall physiotherapy regime, according to Michael Kay, a physiotherapist and former chair of acupuncture for the Canadian Physiotherapy Association.
“Most physiotherapists use cupping as an extension for muscle relief,” said Kay.
“Most of the extender muscles are very tense on swimmers. Sometimes cupping is used to get a lengthening effect, which could be used as a pain management technique.”
According to experts, increased blood flow is believed to help the body recover faster. Cupping is also used by some as a form of pain relief (although the treatment is said to be a little painful itself).
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Of course, one of the downsides of cupping is the deep purple or red marks that are left behind.
This is caused when the suction ruptures small blood vessels at the surface of a patient’s skin. (And, yes, it’s technically the same thing that happens when someone gives you a hickey.)
While the marks may look painful, some only experience mild discomfort after treatment. According to Kay, the marks fade a few days post-treatment.
What does cupping help with?
Kay said cupping is almost always used by physiotherapists as a deactivation of pressure points. Patients who are offered cupping might be suffering from a muscle strain, or pain due to overuse.
“There could be pain problems with the joint and the muscles are in a protective spasm and you might be using the cupping to stretch out those muscles gently,” he said.
Physiotherapists and acupuncturists almost always use cupping as a follow-up treatment to something else, whether it be massage or deep rolling. However, Chinese medicine practitioners often use cupping on its own as a targeted treatment.
Does it actually work?
Phelps isn’t the only athlete to believe in the technique. Several other Rio athletes and even celebrities like Gwyneth Paltrow have been spotted with the marks in the past. However, scientific studies don’t provide any sound evidence as to whether or not cupping really works.
A 2012 study involving patients with arthritic knee pain found that those who underwent cupping therapy reported less pain after four months than those who didn’t receive the treatment.
However, researchers noted that those who received cupping knew they were receiving treatment, which could mean there was risk for a placebo effect.
Another 2012 study looked at 61 patients suffering from chronic neck pain. Half of the group received progressive muscle relaxation (PMR) therapy and the other half underwent cupping twice a week for 12 weeks.
While both groups reported less pain overall, those who were treated with cupping said they felt less pain during treatments.
But, the study did note that one treatment isn’t superior to the other.
Kay believes one of the reasons cupping might be more popular among athletes and Olympians is that they are more open to alternative therapies because they can’t take pain medication.
“Most people are reluctant to take medication and, in this case, athletes can’t. So they rely on physiotherapy,” he said.