Does cupping reduce muscle fatigue?
In the Rio Olympics, a number of athletes, notably Michael Phelps, were sporting big, perfectly round hickeys—manifestations of the ancient art of cupping.
If you are not familiar with cupping or want to see the skin distortion achieved, watch this YouTube video. The reduced pressure on the skin breaks capillaries, creating an eccymosis—so called myofascial decompression therapy. Cupping has been around for at least 3000 years, and current articles in the medical literature purport its effectiveness for treating everything from menstrual cramps to acne to hypertension.
I have also heard cupping described as negative pressure therapy. There is no such thing as negative pressure. Outer space is a close as you can get, and that is zero pressure. So cupping reduces but does not negate pressure.
Myofascial is also a misnomer. The proponents have no idea what happens to the muscle and fascia beneath the cup. It is more accurate to call it skin decompression therapy.
Then I have my doubts, as do many others, about the claim that cupping brings more blood to the underlying fascia and muscles and hastens recovery from muscle fatigue. Of course, blinded studies are impossible, and skin bruising does not automatically imply any change in the pressure, capillary permeability, or blood flow to underlying muscles. For one thing, fascia is nearly avascular, so bruising or hyperemia there would be minimal. Furthermore, if increased blood flow to aching muscles is the goal, wouldn’t a hot pack or Jacuzzi work as well? For one thing, those modalities cover larger areas.
So, what does the literature say? The only recent article that had the magic words, randomized controlled trial, was this one:
Investigators in Taiwan randomized 60 patients who had experienced neck and shoulder pain for at least 3 months into two equally sized groups. The treatment group received cupping for 10 minutes at three right-sided acupuncture points on their backs and for 10 more minutes at symmetrical sites on the left. The control subjects sat quietly for 20 minutes.
Skin surface temperature, systemic blood pressure, and visual analog scale scores for pain were obtained from each subject before and immediately after the test period.
RESULTS: Skin surface temperature increased at the cupping sites by an average of about 2 degrees C and did not change at the identical acupuncture sites in the control group. Blood pressure dropped by about 6 mm Hg in the cupped group and by about 4 mm Hg in the control group—a statistically insignificant difference. Pre-study neck pain visual analog scale scores were 9.7 in both groups and dropped to 3.6 in the cupped group and to 9.5 in the control group—a statistically significant difference. Pre-study shoulder pain was 8.5 in both groups and dropped to 2.6 in the cupped group and to 7.9 in the control group—also a statistically significant difference.
DISCUSSION: The authors discuss that cupping causes hyperemia in the skin, which creates a sensation of warmth. They do not speculate on how this easily observed effect reduces pain, which is presumably coming from fascia, muscles or joints.
COMMENT: Even though this was a randomized, controlled study, I wish that the investigators had included another group of patients who received hot packs in the same locations for the same length of time. I also wonder what the placement of just one or two cups would have achieved compared to the six that were used. Then, what was the effect of cupping an hour, day, or week later?
So skin hyperemia relieves pain, at least momentarily. That comes as no surprise. What does it do for Michael Phelps’ muscle fatigue? That question remains unanswered.
Here is a review article that you might find interesting. The full text of this one is also free.