Scre_15_127.266_271.tp

Journal of Strength and Conditioning Research, 2001, 15(2), 266–271 ᭧ 2001 National Strength & Conditioning Association Brief Review
Acupuncture in Human Performance
THOMAS W. PELHAM,1 LAURENCE E. HOLT,2 AND ROBERT STALKER3
1Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada; 2School ofHealth and Human Performance, Faculty of Health Professions, Dalhousie University, Halifax, Nova Scotia,Canada; 3Sport Medicine Clinic, Dalhousie University, Halifax, Nova Scotia, Canada. ABSTRACT
cal, nutritional, and pharmacological commoditieshave been classified as ergogenic aids.
To this point in time, acupuncture has been used primarilyas an analgesic, a therapeutic intervention that controls pain Advances in training methods (e.g., warm-up, al- under pathological conditions. Although some of the mech- titude training), strategies (e.g., planned plays), new anisms of acupuncture as it applies to pain relief have been features in equipment (e.g., aerodynamically designed studied, little is known of the positive and/or negative ef- clothing), nutritional routines (e.g., vitamin supple- fects of this procedure on the physical performance param- ments, precompetition carbohydrate loading), pre- eters of healthy people, particularly highly trained athletes.
scription drugs (e.g., beta-blockers), and nonprescri- After introducing acupuncture from historical and technique bed drugs (e.g., caffeine) are considered ergogenic aids viewpoints, preliminary studies of the effects of acupuncture by many sport health professionals and sport scien- on strength, aerobic conditioning, flexibility, and sport per-formance are discussed, as well as concerns regarding the tists. Also, both prescription (e.g., amphetamines) and direction of research investigating the potential benefit and/ illegal drugs (e.g., cocaine) have been used as ergo- or adverse effects of this practice. Finally, an argument is put genic aids. In the past few years, the most publicized forward for the establishment of guidelines for the use of banned ergogenic aids have been anabolic-androgenic acupuncture in the sports community.
steroids, steroid precursors such as androstenedione(i.e., Andro), and blood doping. Although steroid useand blood transfusions are important in many medical Key Words: ergogenic aids, exercise physiology, sport
treatments, their use in sport is considered a serious violation of the rules. Andro, although banned from Reference Data: Pelham, T.W., L.E. Holt, and R. Stalker.
Olympic events and some professional sports, can be Acupuncture in human performance. J. Strength Cond. purchased over the counter in the U.S.A. and is the focus of much research and speculation (15).
Although not classified as ergogenic aids, a num- ber of hands-on techniques, such as massage (e.g., su-perficial/deep), proprioceptive neuromuscular facili- Introduction
tation (PNF) stretching and direct pressure, have been Virtually all athletes and coaches are involved in a employed extensively and are believed to be useful in
constant search for ways to improve performance preventing injuries and hastening recovery and pos- and gain a competitive edge over their rivals. Unfor- tunately for many, this has led to a win at all costs Holistic medicine has gained popularity recently, philosophy that seems to be pervasive, particularly at and a number of alternative medical interventions the ‘‘upper’’ levels of sport. Many athletes are willing have emerged with possible performance-enhancing to use any substance, technique, or practice, either properties. One such candidate currently under inves- based on science or exaggerated belief, without a full tigation is acupuncture, which has been a medical in- understanding of either the short-term or long-term tervention in the Orient for over 2,500 years. Although ethical, legal and health implications of their actions.
conventional western medicine has been slow to em- Applications and methods (aside from training it- brace acupuncture, this ancient form of therapy has self) that improve the critical physiological and bio- been prescribed for a wide variety of medical condi- mechanical variables associated with sport perfor- tions in the Far East. However, in the west, the role of mance or remove factors that limit physiological ca- acupuncture as a treatment option has expanded dra- pacity have been defined as ergogenic aids (1, 2). A matically since the 1970s to include neurologic (20), large assortment of mechanical, physical, psychologi- respiratory (13), and orthopedic (5) conditions. In all probability, this trend will continue as health care be- der. Although the study of anatomy by autopsy was not permitted in ancient China, clinicians used phys- In the Canadian clinical setting, many certified iological observations to develop the theory of the physical therapists use acupuncture primarily for pain functions of Zang and Fu organs. The functions of the modulation. Controlling pain could be a considerable Fu organs were to receive and digest food (31). Their competitive advantage for athletes in most sports and role was then to transmit the nutrients to the Zang should be one of the foci of future research.
organs, which were to produce and store energy (31).
The side effects of acupuncture have been found to Central to traditional Chinese medicine (TCM) is be few and mild. However, in some sports, these side the notion that energy flows throughout the body effects (e.g., some individuals may experience dizzi- along specific channels, or meridians. The movement ness) (28) could place the athlete at risk. During com- of biological energy along these meridians and their petition, this condition could negatively affect the ath- collaterals connect and communicate between the vis- lete (e.g., downhill skier) placing him/her in a hazard- cera and extremities. It is through these channels that ous situation. Given this possibility and the experi- the physiological functions of the body are regulated mental tendencies of athletes and coaches in their and equilibrium is maintained. There are 12 principle quest for a competitive edge, it seems quite possible meridians, 6 each from the Zang and Fu organs. Me- that misapplication of this procedure may emerge. In ridians are bilateral and run both a superficial and order to prevent a repeat of the many problems en- deep course. Specific acupuncture points are located countered with the improper use of other ergogenic along each meridian. It is at these points that acu- aids, it is important for all athletes, coaches, sport sci- puncture needles are inserted. The purpose of the me- entists, and sport health professionals to have a full ridians is to distribute visceral energy to all tissues of understanding of the various practices of alternative the body. The acupuncture meridian system is used to medicine, including acupuncture. Stimulation of spe- make diagnoses and to develop treatment plans for a cific acupoints have been suggested to improve phys- wide variety of pathological conditions. As mentioned ical performance in sport (12, 21, 33).
above, along with the meridians, other internal factors, With this in mind, the following discussion will Yin-Yang, energy, blood, and Zang-Fu organs must re- center on the influence of acupuncture on athletic per- main in balance to maintain health. As well, the body formance with special reference to strength, aerobic must be in harmony with external (environmental) fac- tors to maintain health. In the event of an imbalance,and based on the diagnosis, specific acupuncture Historical Aspects of Acupuncture
points are stimulated to restore equilibrium.
The ancient Chinese believed that everything in nature Acupuncture Techniques
was energy, or Qi. Further, Qi was systematically di-vided into Yin and Yang and symbolized by the sign From the oriental perspective, the goal of acupuncture of TAO (31). The ancient philosophers of China be- is to re-establish the balance of internal body energies.
lieved that disease was a result of an imbalance be- Internal factors, such as emotion, stress, injury, and tween Yin and Yang. According to Taoistic Chinese external factors, such as cold and heat, can disrupt the philosophy, Yin and Yang have an antagonistic rela- tionship, (if one increases, the other must decrease) Over the centuries, treatment plans have been de- (31). Another belief of the ancient Chinese was that the veloped for pathological conditions. But little is known basic materials for life were: wood, fire, earth, metal, of the uses of acupuncture for the enhancement hu- and water (31). These Five Elements were interrelated and everchanging. The physicians of ancient China ap- The most striking feature of acupuncture is the in- plied these beliefs to the health of the body. The 6 solid sertion of needles into specific points on the human Zang organs were: heart, spleen, lung, kidney, liver, body. In the clinical setting, the number of points, du- and the pericardium (31). The 6 hollow Fu organs ration of the treatment session, and the duration of the were: small intestine, stomach, large intestines, urinary treatment program are based on both the identified bladder, gall bladder, and triple warmer (31). From pathology and training/experience of the practitioner.
ancient times, the triple warmer has been referred to Although there are mandatory standards and as ‘‘having a name but no form’’ (31). The triple warm- guidelines with regard to safety, there appears to be er consists of 3 parts; the upper warmer, which is the no fixed treatment protocol. Selection of points, type head and chest region, and functions include the heart of stimulation, amount of stimulation at each treatment and lungs. The middle warmer extents from the chest session, the number of treatments per week, and the to the umbilicus, and functions of the stomach, liver, total number of treatment sessions will vary. That is, and spleen. The lower warmer region is the lower ab- as mentioned above, the selection of acupuncture domen, and functions of the kidneys and urinary blad- points and treatment protocols are based on the spe- cific diagnosis. However, there would appear to be a caused by vigorous exercise can disrupt these merid- degree of variability among authors and practitioners ians, interfering with energy flow and circulation.
on which points and treatment protocols are used for They state that ear point-specific acupuncture can ‘‘un- any particular disease. Needle selection and criteria for block the meridians’’ and thereby attenuate fatigue.
usage vary between acupoints and are dependent on The goal of TCM acupuncture is to insert needles into a number of factors including treatment method, most specific acupuncture points along these meridians at- notably the desired depth of penetration of the needle.
tempting to re-establish the flow of energy and return Variable treatment parameters are used by the physical therapist in the Province of Nova Scotia and dictated In western medicine, both the classical approach by the current state of the pathological condition and and a neurophysiological/neurochemical approach are used, and in the latter approach, needles are inserted Generally, the length of the needle used is deter- into specific points that are associated with nervous mined by the desired depth of insertion and the pur- tissue that activate specific muscles. By stimulating pose of the treatment. Commonly used sizes by Nova these points with needles, ␤-endorphins are released Scotian physical therapists are 25–40 mm with a di- ameter of 0.22 mm. In the Nova Scotian physical ther- Along with altering pain sensation, exercise and apy setting, needles are thin, sterile, and disposable.
acupuncture can be beneficial by having a positive ef- These needles are encased in plastic tubes.
fect on mood states (3). Optimal performance has been During acupuncture, the individual is placed in a associated with mood (i.e., arousal level) (23).
position of support (usually lying) and comfort, ex-posing the region to which the needle will be inserted.
Acupuncture and Strength
Before insertion into the skin the area is cleansed withalcohol. The patient may feel a sensation as the needle Acupuncture, particularly electroacupuncture, is felt to pierces the skin. A popular adjunct is stimulation of be able to produce the same excitatory characteristics the needle either manually or with electrical current.
within the motor nerve and muscle as does exercise(3). Electrical stimulation is a common procedure used Acupuncture, Pain, and Physical
by physical therapists to increase strength in atrophied Performance
muscle. The question then arises as to whether acu-puncture can increase strength and to what extent? A noxious event, such as an insult to tissue can activate In the popular literature, acupuncture has been ad- nociceptors (pain receptors) (19). Stimulation of noci- vocated as an adjunct to hypertrophy training (i.e., ceptors generate impulses that are transmitted to the bodybuilding); a means to develop specific muscle central nervous system (CNS) where the incoming sig- groups; a way to accelerate recovery from both work- nals are processed in the diencephalon and pain is outs and injuries; and as a stimulant for growth hor- perceived. However, these transmissions can be inhib- mone and testosterone production (25). In regards to ited (24). Acupuncture has been suggested to be as- aesthetics, it has been suggested that ‘‘acupuncture sociated with the release of ␤-endorphins (26). These stimulates facial muscles to contract and strengthen al- opiates have been identified with pain modulation and most immediately’’ (16). This application seems to be nociceptive transmission inhibition at all levels of the without foundation, as a review of the literature failed nervous system. Both exercise and acupuncture stim- to reveal any controlled studies investigating the use ulate afferent nerve fibers. The A-delta and C fibers of acupuncture for body hypertrophy or any of the are possible targets (3) and have been shown to be pathways for pain sensation. The hypothalamus and Muscle activity and potential changes in strength other brainstem nuclei have been suggested as possi- following acupuncture have been examined in one ble sites affected by acupuncture (3).
study. Concentric and isokinetic strength and endur- Increased concentrations of ␤-endorphins have ance were tested using a hand dynamometer and a been found following both exercise and application of leg extension isokinetic dynamometer in 17 young acupuncture. ␤-Endorphins have been associated with healthy men postacupuncture (34). A single needle long-lasting pain control. As well, acupuncture has was inserted for 15 minutes into either a flexor muscle been hypothesized to attenuate the sympathetic sys- of the wrist or the semitendinosus muscle. Although muscle endurance or muscle strength test scores did As mentioned earlier, the philosophy underlying not change, electromyography recordings were differ- TCM is based on the notion that the healthy human ent following acupuncture for the stimulated semiten- body is in a balance of energy. Further, energy flows dinosus muscle during the strength test and the non- through the body in well-marked pathways, or merid- stimulated semitendinosus muscle during the endur- ians. Illness and pain can disrupt this balance. As well, ance test. The investigators suggested that acupunc- Jaung-Geng et al. (12) have hypothesized that fatigue ture is able to influence neuromuscular activity (34).
However, a serious confounding variable in this study controls. Overtraining in distance runners as inter- was the fact that the needle was inserted into the belly preted through a TCM approach would indicate that of the muscle and not into specific acupuncture points.
exhaustive training with inadequate recovery results Therefore by definition, this treatment in fact was not in an energy imbalance, inducing obstructions of the meridians, leading to illness and disease (deficiency Exercise and acupuncture have been reported to syndromes) (27). Point-specific acupuncture can be have several common physiological effects on the hu- used to re-establish the energy flow through the me- man body. Physical exercise and acupuncture have ridians, thus relieving the symptoms of overtraining.
been suggested to attenuate the nervous system and The use of acupuncture to treat exercise-induced to produce similar effects (described below) on the musculature pain has been studied (6, 32). A highly cardiovascular and pulmonary systems, along with trained young runner was forced to restrict training as producing similar neuroendocrine responses (3).
a result of experiencing pain in the lower anterior ab-dominal region during workout sessions. Standard Acupuncture and Aerobic Conditioning
treatment had failed to correct this problem. For thefirst 3 weeks, the runner was treated once per 3-day In endurance sports, such as long distance swimming, cycle followed by 1 treatment per week for 4 weeks.
cross-country skiing, and the marathon, superior aer- Acupoints used in various combinations over the treat- obic capacity has been identified as a critical factor to ment period were: Pc 3, Lv 14, St 36, Sp 9, Lv 2, and high level performance (22). Oxidative capacity is de- Sp 3. Through TCM the runner was able to resume termined by how efficiently oxygen is delivered and utilized by the active tissue. A common method used Neural involvement in hemodynamics is an im- by sport scientists to investigate oxygen delivery and portant factor that must be taken into consideration utilization is direct or indirect submaximal, or maxi- while preparing from sport competition. The demands placed on the autonomic system during intense sport- ing, a variety of metabolic, cardiovascular, and pul- ing activities can limit physical performance. Acu- monary factors are measured. This approach has been puncture has been shown to have autonomic effects used in a number of studies where acupuncture was (both sympathetic and parasympathetic) on central administered before testing (7, 14).
cardiac function (17) and peripheral circulation (35).
Karvelas et al. (14) measured heart rate, ventilation, Research has reported that properly prescribed acu- ventilatory equivalent for oxygen, respiratory ex- puncture can decrease heart rate and increase stroke change ratio, and oxygen uptake during continuous volume leading to a more efficient cardiac output (17).
submaximal or maximal cycle ergometer exercise in Athletes who have lower heart rates and higher stroke healthy individuals after a single bout of acupuncture.
volumes at various workloads have a clean advantage Karvelas et al. (14) used bilateral acupoints Li 13, P 6, over competitors in sporting activities where cardio- S 36, Sp 6, and unilateral acupoints Cv 20 and Co 15.
respiratory endurance is an important factor.
Needles were sterile, disposable stainless steel. Diam- Acupuncture has been shown to be associated with eter and length of the needles were either 0.25 ϫ 50 vasodilatation of the peripheral system leading to pe- mm or 0.20 ϫ 30 mm. They found no significant ripheral resistance and blood pressure reductions and changes in any of the physiological parameters.
blood flow increases (17). Explanations range from ac- Measurements of blood lactate during submaximal tivation of efferent vasodilator fibers to point-specific and maximal exercise can provide some insight into acupuncture stimulation of reflexive autonomic vaso- the aerobic potential of the athlete. Two specific points on the lactate accumulation versus workload curveused by sport scientists are the lactate threshold and Acupuncture and Flexibility
onset of blood lactate (Lt) accumulation (OBLA).
Reaching OBLA at a lower percentage of aerobic up- Flexibility is important in sport performance. Physical take is a favorable outcome for the athlete. Ehrlic and therapists, sport scientists, and sport medicine physi- Haber (7) investigated the influence of acupuncture cians and coaches share a commonly held notion that administered once per week over a 5-week period on achieving adequate degrees of flexibility may prevent anaerobic threshold and work capacity during exercise or reduce injuries (9, 10). Maintaining sufficient flexi- in healthy young, untrained males. These investigators bility is related to efficient musculoskeletal function.
(7) found that individuals in the acupuncture treat- Decreases in relative flexibility can lead to tissue dys- ment group had higher maximal exercise capacity and function and a wide range of problems (11).
were able to perform higher workloads at OBLA than Physiologic and morphologic factors influence flex- individuals in the placebo group. As well, individuals ibility (8). The level of motor unit activity will influ- who received acupuncture demonstrated lower heart ence muscle tension, as will the viscoelastic properties rates at various submaximal and maximal levels than of the surrounding fascia (8). Both will affect the de- gree of flexibility surrounding a particular joint. A va- sign surrounding these improvements would add in- riety of active and passive stretching techniques are formation that sport governing bodies could use to de- used to elongate taut tissue. Unlike static and ballistic cide whether or not acupuncture should be considered stretching, PNF stretching relies heavily on neural in- an acceptable adjunct to training. Research may also put to relax and elongate soft tissue (29, 30). Acu- determine the effectiveness of acupuncture as a pro- puncture, because of its influence on the nervous sys- phylactic in high performance sport.
tem can be used as an attenuating agent in combina- Athletic performance is determined by a number of tion with PNF stretching to increase joint-specific flex- factors, with their specific contribution varying from ibility. This is a common treatment combination used sport to sport. For example, long distance running is by the senior author to increase range of motion a simple, repetitive skill with high aerobic power de- around a joint. As mentioned earlier, acupuncture has mands, whereas baseball consists of a set of complex been shown to alter electromyographic activity of a skills requiring a high level of neuromuscular coordi- stimulated muscle; therefore it has the potential to nation and relatively low to moderate levels of mus- change the tension within the muscle, allowing the cular endurance and cardiovascular conditioning. The muscle to relax and elongate (9, 10). The additional ergogenic effects of acupuncture on different sports analgesic effects of acupuncture to combat myofascial must be evaluated on an individual basis.
pain usually associated with taut myofasia, as well as On the other hand, identifying the potential health exercise-induced muscle soreness (6), lend support for risks associated with acupuncture while participating in vigorous physical activities or training is required.
Fifteen subjects with acute Torticollis were treated Scientific information regarding the dangers and con- with electroacupuncture (4). All subjects reported pain traindications for the use of acupuncture on highly with cervical spine movement and demonstrated re- trained athletes is a prerequisite before accepting acu- duced range of motion of the cervical spine. On av- puncture for performance enhancement. Furthermore, erage, after 4.5 treatment sessions, subjects reported a governing bodies can design acceptable procedures marked reduction in pain with a decrease in muscle and conditions for acupuncture use. Designing appro- spasm. One postulated mechanism by the authors was priate standards of conduct and practice for the use of that the electrical current dilated the postcapillary acupuncture and developing ethical and legal guide- sphincters of the muscles in spasm, increasing local lines for each sport should be a priority for sport circulation and thereby, decreasing the muscle spasm health professionals, sport scientists, coaches, and ath- Sixteen subjects with a variety of rotator cuff ten- dinitis and inflammatory capsular conditions received Practical Applications
acupuncture to the shoulder region (18). The acupointsused were determined based on the pathological con- The impact of acupuncture on specific strength and dition. Most noticeable symptoms were pain with conditioning training methods—modes, training in- shoulder movement and decreased shoulder move- tensities, frequencies, volumes, and rest intervals— ment. Along with acupuncture, manual physical ther- needs further investigation. Of special interest would apy techniques were used. Patients reported less pain be the effects of acupuncture on the neuromuscular with shoulder movement and an improvement in the components of speed-endurance and plyometric train- activity of the shoulder following treatment (18).
More information is required concerning the effects Some Concerns to Consider
of acupuncture on muscle physiology and bioenerget-ics. As well, research is needed to investigate the car- The significance of acupuncture in enhancing perfor- diovascular, respiratory, neuroendocrine, and neuro- mance remains controversial. One reason is that there muscular responses to acupuncture in association with are few controlled studies in this area. We simply do resistance, aerobic, and flexibility training and sport- not know the positive and/or negative aspects of acu- puncture applied to highly trained athletes. However, The combination of acupuncture and various die- it would seem prudent to avoid the situation that de- tary and nutritional programs with regard to weight veloped in the mid-1980s, where blood transfusions gain or loss and exercise metabolism would be of in- were banned by the International Olympic Committee terest to many athletes and strength and conditioning after the 1984 Olympic Games, even though there was coaches in weight control sports such as rowing, box- no method of unambiguous detection. To avoid such ing, and gymnastics. The effects of acupuncture on a problem further research with regard to the use of emotion would be helpful to athletes desiring more acupuncture in sport performance is essential. Defin- control of anxiety, arousal, and selective attention.
ing what, if any, improved physiological parameters If acupuncture has sport-enhancement properties, are associated with acupuncture and the treatment de- the proper and safe match of acupuncture points and treatment regime with sporting event or skill can only stenedione on serum and adaptations to resistance training: A be obtained with further study. This information randomized controlled trial. JAMA 281(21):2043–2044 1999.
16. LATONA, V. About face. Vegetarian Times November:92–96 1998.
would allow the athlete, strength and conditioning 17. LEE, D.C., M.O. LEE, D.H. CLIFFORD, AND L.E. MORRIS. The au- coach, sports scientist, and health care provider knowl- tonomic effects of acupuncture and analgesic drugs on the car- edge required for informed decisions as to the moral, diovascular system. Am. J. Acupuncture 10(1):5–30 1982.
ethical, and legal boundaries of acupuncture as an en- 18. MARCUS, A., AND R.I. GRACER. A modern approach to shoulder pain using the combined methods of acupuncture and Cyriax- hancement aid in designing strength and conditioning based ‘‘orthopaedic medicine.’’ Am. J. Acupuncture 22(1):5–14 programs for performance enhancement.
19. MELZACK, R., AND P.D. WALL. Pain mechanism: A new theory.
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