Myofascial Cupping Therapy for Pain, Recovery and Performance: Evidence & Proposed Mechanisms

The Rio 2016 Olympic Games came to an end with the United States bringing home more medals than any other country. More specifically, the U.S. earned 46 gold medals, almost twice as many as runner-up China, with 26 gold medals.¹ In all fairness, part of the U.S. dominance in this year’s Olympics may have in part been due to the large number of Russian athletes that were banned from the games for using performance-enhancing drugs.³ While the scandal decimated the Russian Olympic team, it also reminded athletes across the world about the importance of fairness in sports and competition. However, given the number of sports in the Olympics where seconds and fractions of seconds decide gold versus silver medals, the scandal also likely pushed athletes to consider other, ethical ways of gaining a competitive advantage. During the Rio Olympic Games, there was perhaps no better example of this than the use of myofascial cupping therapy by some of the elite athletes.

As reported by USA Today⁴ and the New York Times,⁵ top athletes such as Michael Phelps and gymnast Alex Naddour were utilizing cupping therapy for recovery, pain relief, and to boost performance. According to Ted Kaptchuk,⁶ a professor of medicine at Harvard Medical School, while cupping is rooted in traditional Chinese medicine, it is not new to the U.S., as cupping was commonly practiced by American physicians in the 18^th and 19^th centuries. Moreover, it is perhaps notable that Keenan Robinson, a strength and conditioning coach, introduced Michael Phelps to cupping after seeing Chinese physical therapists using it at the Pan Pacific Championships to facilitate recovery.⁷ That is, it would seem that, in the main, Western-based coaches and health care practitioners, including physical therapists, have made the Asian tradition of cupping therapy popular among elite athletes. Therefore, a better understanding of the history, proposed physiologic mechanisms, indications, contraindications and support from the literature of cupping is appropriate.

In recent years, the integration of traditional therapies into modern wellness practices has gained considerable attention, especially among athletes seeking ways to improve performance and speed up recovery. A holistic treatment plan often includes a combination of therapies designed to target both physical and mental well-being, addressing the root causes of discomfort rather than just the symptoms. Cupping therapy has proven to be an effective part of such plans, helping athletes by improving circulation, reducing muscle stiffness, and promoting overall recovery. However, it is rarely used in isolation; many find that pairing it with other holistic treatments, such as shiatsu massage, provides a more comprehensive approach to health. Shiatsu works by applying pressure to specific points on the body, which enhances energy flow and further supports muscle relaxation and recovery. This combination of cupping and shiatsu can optimize the healing process, complementing each other by addressing both the physical and energetic aspects of an athlete’s body.

HISTORY OF CUPPING THERAPY

The origin and historical progression of cupping is important to understand as cupping is thought to date back as early as 3000 BC, with evidence of utilization in ancient Chinese, Hindu and Egyptian medical scriptures.^8,9 In 1920, the Journal of the American Medical Association found that cupping provides a mechanism of counterirritant and edema control.¹⁰ Yet, researchers in 1983 and 2004 suggested a psychosomatic theory or “placebo effect” of cupping,⁹ and fast-acting pharmaceutical drugs became much more popular to address pain. Effective non-pharmaceutical treatments for musculoskeletal disorders, such as cupping, were consequently forgotten or dismissed by conventional Western medicine,⁷ while Eastern cultures continued to embrace the technique. Chinese and Russian practitioners conducted research attempting to confirm the broad usage and clinical efficacy of cupping,⁹ and a 2006 Korean study reported that cupping therapy was utilized by 93.5% of 6,708 physicians practicing Oriental medicine.⁹

RISKS AND CONTRAINDICATIONS

Cupping is considered a relatively safe intervention with very few documented adverse events, most involving minor and transient injuries caused by practitioner negligence and inappropriate duration of treatment. Common side effects of cupping include minor erythema, edema, ecchymosis, and hyperemia.^{9, 11} While no cases have been documented, wet cupping introduces additional risk of exposure to blood-borne pathogens and transmission of infectious diseases.⁹ However, wet cupping techniques are not frequently utilized by Western-based practitioners.

As with other types of instrument-assisted manual therapy (e.g. dry needling), it is important to take a thorough patient history in order to identify relative and absolute contraindications that may preclude the use of the treatment in question. Caution should be exerted when considering cupping on individuals with low blood pressure, as they have an increased susceptibility to fluctuations in blood pressure, and on patients with thin skin.¹² Precaution should be taken when performing cupping immediately following injury or surgery, as cupping may influence the body’s natural physiologic reaction to rush synovial fluid and blood to the site.¹¹ Cupping therapy is contraindicated for individuals with connective tissue disorders (e.g. Ehlers-Danlos syndrome), fracture, malignancy; in addition, cupping should be avoided at the site of a hernia or deep vein thrombosis, during pregnancy, and at areas of skin damage or open wounds.¹¹

PROPOSED MECHANISMS OF CUPPING

The theoretical constructs surrounding the use of cupping differ significantly between Eastern and Western healthcare practitioners. Cupping in the Eastern, traditional Chinese, or Oriental medicine model is believed to address stagnant or blocked qi that causes disease; furthermore, wet cupping uses scarification, a technique that combines a small incision with bloodletting,¹³ to remove blood and associated toxins.⁷ In contrast, Western-based cupping (dry cupping) uses plastic, silicone, or glass cups with a vacuum seal to influence myofascial tissue physiology.⁷ Unlike the compressive forces that are typically applied during other forms of manual therapy (e.g. massage, joint mobilization, Graston®), negative pressure within the cup visibly lifts the skin away from the body. 

The biomechanical and neurophysiological effects of myofascial cupping remain theoretical. Tensile load in the center of the cup and the compression of tissues at the rim of the cup transmits forces through the connective tissue layers to the muscle itself.¹⁴ Tham et al¹⁴ found maximum stress with cups larger in diameter, thus exerting more force on the tissue being treated. When the loose connective tissue layers, including the aponeurotic layer and epimysium undergo mechanical stress, the overall temperature of the tissue increases, reducing the viscosity of hyaluronic acid polymers, thereby decreasing the adhesive properties of the tissue. In this way, cupping may lead to improved fascial gliding, facilitating cellular mechanotranduction.^15,16 A number of studies have demonstrated that mechanotransduction stimulates fibroblast proliferation and collagen synthesis, which actively contribute to the viscoelastic nature of the symptomatic tissue via a rho kinase-dependent mechanisms.^17-20 In this way, mechanotransduction may dampen tissue tension via actin polymerization, leading to better cytostructural repair.^{17, 19-22}

A number of research teams have compared the physiologic actions of cupping with those responsible for negative pressure wound therapy, often referred to as vacuum assisted closure.²³ According to Kucharzewski et al,²³ the Greeks performed cupping with heated copper bowls for wound healing in as early as 400 BC. Furthermore, Mehta et al²⁴ suggested cupping may improve microcirculation,^{25, 26} endothelial repair,²⁵ granulation^27,28 and angiogenesis²⁹ of local tissue, thereby clearing metabolic toxins,^30,31 and increasing pressure-pain thresholds.³² In addition, Masuda et al³³ reported increased intramuscular vasodilation and microcirculation following cupping.³⁴ Nevertheless, a recent study using infrared thermal imaging demonstrated an initial reduction in localized skin temperature following dry cupping, which did not rise above the baseline temperature until 10 minutes post-treatment.³⁵ Emerich et al³⁴ further measured a significant increase in the lactate-pyruvate ratio of symptomatic subcutaneous and muscle tissue via microdialysis, indicative of anaerobic metabolism 160 minutes after cupping treatment.

In short, while symptomatic muscle has been shown to have decreased blood flow and increased lactate levels,³⁶ myofascial cupping appears to temporarily exaggerate the condition so as to “kick-start” the physiologic changes necessary to “reset” the tissue.³⁴ By propagating the tissue’s hypoxic state, more lactate is produced, thereby increasing the acidity.³⁴ In skeletal muscle, the added acidity has been shown to combat fatigue³⁷ and stimulate nitric oxide release, resulting in improved microcirculation and blood flow via vasodilation.³⁸ Importantly, Emerich and colleagues did not measure increases in lactate until 160 minutes following cupping treatment.³⁴ Therefore, the metabolic changes were independent of short-term pain reduction following cupping, but they may facilitate more long-term improvements by altering the environment of the tissue.^{34, 39} In this context, cupping may also help combat the physiology associated with myofascial trigger point formation by reversing the hypoxic environment mediating the energy crisis originally described by Travell and Simons^{40, 41} and developed by Gerwin.⁴²

The tensile stress of cupping likely causes small, superficial capillaries of the skin to dilate and leak, causing blood to seep into the tissues and produce ecchymosis.¹⁴ In a small trial of 6 patients with various medical conditions, investigators noted small fluctuations in red and white blood cells, uric acid, rheumatoid factor, pH and hemoglobin levels following 14 days of cupping therapy.¹² In addition, the patients had a significant (15% to 175%) reduction in their erythrocyte sedimentation rates (ESR), indicative of a systemic reduction in inflammation secondary to cupping.¹²

Cupping is reported by many clinicians to reduce pain and increase pressure-pain thresholds in athletes with myofascial pain and/or localized myofascial trigger points with the effects comparable to other instrument-assisted soft-tissue mobilization (e.g. Graston®) and ischemic compression techniques.⁴³ Perhaps the most compelling analgesic mechanism for cupping therapy is the activation of A-delta fibres, A-beta fibres, and C-fibres, which inhibit afferent input to the dorsal horn.³⁴ Cupping-mediated analgesia may also contribute to the activation of mechanoreceptors in the periphery, resulting in the release of endogenous anandamide and opioids.^7,11,14 Like needle manipulation during acupuncture, cupping may further provide enough mechanical stimulation to activate TRPv1 receptors on peripheral nerve endings, propagating an intercellular Ca2+ wave and expelling ATP via pannexin channels, which break down adenosine.⁴⁴ Interestingly, Takano et al reported a significant increase in interstitial adenosine following acupuncture with needle manipulation (i.e. winding),⁴⁵ which activates A1 adenosine receptors located on nerve endings,⁴⁶ afferent nerves,⁴⁷ and pre-synaptic DRG terminals,⁴⁸ resulting in anti-nociception—i.e. pain reduction. As G-protein coupled receptors, A1 receptor activation is thought to work by inhibiting adenylyl cyclase, attenuating cAMP and phospholipase C.⁴⁵ Since an increase in cAMP is associated with chronic pain, the inhibition of adenylyl cyclase is noteworthy.⁴⁵

CUPPING FOR CHRONIC PAIN

According to Tham et al, the therapeutic benefits of cupping have been “well-documented” for many years.¹⁴ However, very few randomized clinical trials have been conducted to study the clinical efficacy related to cupping. In a systematic review of studies that used dry cupping for low back pain between 1980 and 2013, researchers found significantly greater reductions in pain intensity (VAS) and disability (ODI) for those who received cupping compared to diclofenac.⁴⁹ Moreover, the authors reported a decreased recurrence rate of pain and an improved quality of life.⁴⁹ A meta-analysis of 135 RCTs including wet cupping and dry cupping suggests cupping combined with other treatments may provide the most benefits, specifically ameliorating symptoms in patients with disc herniation and cervical spondylosis.⁵⁰

In a randomized controlled exploratory trial and using a large, adjustable silicone cup over the knee for decompression with a pneumatic device, Teut⁵¹ et al reported significantly greater reductions in pain and disability scores (WOMAC) at a 12-week follow-up compared to controls.⁵¹ Likewise, in a randomized controlled trial, Chi et al,² found significantly greater reductions in neck and shoulder pain (VAS) compared to controls.  Notably, both of these studies^{2, 51} compared dry cupping to resting controls without an intervention. Moreover, in a study of 50 patients with chronic non-specific neck pain, a series of five dry cupping treatments were found to significantly reduce pain compared to wait list control.³⁹ The authors further noted, “Not only subjective measures improved, but also mechanical pain sensitivity differed significantly between the two groups, suggesting that cupping has an influence on functional pain processing.”³⁹ In a controlled trial with a 2-year follow-up of 133 patients with chronic non-specific neck pain, Lauche et al reported significantly greater improvements in function (NDI) and quality of life (SF-36) in the cupping group—that is, the effects of cupping appeared to not decay with long-term follow-up.⁵²

CONCLUSIONS

According to Sackett, “Evidence based medicine is not “cookbook” medicine. Because it requires a bottom up approach that integrates the best external evidence with individual clinical expertise and patients’ choice, it cannot result in slavish, cookbook approaches to individual patient care.”⁵³ Cupping has been used for centuries among both Eastern and Western-based health care practitioners; however, cupping therapy is reemerging as a popular modality for chronic nonspecific neck pain, low back pain, shoulder pain, knee osteoarthritis, and to increase pressure-pain thresholds and perhaps enhance athletic performance in professional⁵⁴ and Olympic athletes.⁴

AUTHORS:

Dr. Clinton Serafino, DPT, Cert. SMT, Cert. DN
Fellow-in-Training, AAMT Fellowship in Orthopaedic Manual Physical Therapy
Physical Therapist, Physical Therapy Center, Monroe, NC

Dr. Michelle Moore, DPT, Cert. DN
Fellow-in-Training, AAMT Fellowship in Orthopaedic Manual Physical Therapy
Physical Therapist, Biomechanix Physical Therapy, Phoenix, AZ

Dr. Thomas Perreault, DPT, OCS, Dip. Osteopractic, MAACP (UK)
Senior Instructor, AAMT Fellowship in Orthopaedic Manual Physical Therapy
Physical Therapist, Hampton Physical Therapy, Hampton, NH

Dr. Raymond Butts, DPT, PhD, MSc (NeuroSci), Dip. Osteopractic, MAACP (UK)
Senior Instructor, AAMT Fellowship in Orthopaedic Manual Physical Therapy
Atlanta, GA

Dr. Michelle Tanner, DPT, Cert. SMT, Cert. DN, FAAOMPT, Dip. Osteopractic
Physical Therapist, Benchmark Physical Therapy, Atlanta, GA

Dr. James Dunning, DPT, MSc (Manip Ther), FAAOMPT, Dip. Osteopractic
Director, AAMT Fellowship in Orthopaedic Manual Physical Therapy
Montgomery, AL

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