Available online at www.sciencedirect.com Cognitive and ScienceDirect Behavioral Practice ELSEVIER Cognitive and Behavioral Practice 16(2009)59-72 www.elsevier.com/locate/cabp Yoga and Mindfulness:Clinical Aspects of an Ancient Mind/Body Practice Paul Salmon,Elizabeth Lush,Megan Jablonski,and Sandra E.Sephton Department of Psychological and Brain Sciences,University of Louisville,Louisville,KY 40292 The use of Yoga and other complementary healthcare interventions for both clinical and non-clinical populations has increased substantially in recent years.In this context,we describe the implementation of Hatha Yoga in the Mindfulness-Based Stress Reduction (MBSR)program of Kabat-Zinn and colleagues.This is embedded in a more general consideration of Yoga's place in complementary healthcare.In providing this overview,we comment on the nature and quality of current research on Yoga,summarize current physiological and psychological explanations of its effects,and discuss practical issues related to teacher training and experience. A.Introduction and Overview about the implementation of these practices-particularly There is a long-standing interest in the health benefits Yoga-in either clinical or research contexts.Concerning of Yoga in India and other non-Western cultures.Yoga is clinical research,studies generally provide little detailed currently experiencing a marked increase in popularity in information about specific intervention elements in terms the West,primarily in health clubs and wellness centers. of either content or process factors,and instead focus One program which has advanced the status of Yoga in attention primarily on outcome measures. clinical settings is the mindfulness-based stress reduction Yoga as discussed here refers to an integrative physical/ (MBSR)program developed by Kabat-Zinn (1990)and spiritual practice which developed in ancient India.We colleagues.This work has stimulated extensive clinical capitalize the word Yoga'throughout in recognition of its practice and research in acceptance-based psychological historical stature as a highly evolved cultural system of interventions in recent years (Germer.2004:Haves and beliefs and practices,even though clinical applications Feldman,2004).Outcome studies reviewed elsewhere tend to 'de-contextualize'it from its cultural and spiritual (Baer,2003;Salmon,Sephton,Weissbecker,Hoover, roots.The word Yoga'means 'yoke'or 'union'and Ulmer,Studts,2004)attest to its promise as a clinical connotes the interconnection of mind,body,and spirit. intervention.A meta-analysis of health benefits associated Yoga practice in Western contexts involves sequences of with MBSR (Grossman.Niemann,Schmidt.Walach. postures,called asanas,that incorporate regulated breath- 2004)reached a similar conclusion,but noted a relative ing and focused attention.Ongoing practice is reported absence of methodologically rigorous studies,and a lack by practitioners to promote psychological well-being and of detail concerning intervention specifics. a variety of physical benefits.Although the focus in Indeed,much of the writing about mindfulness Western Yoga practices is usually on the asanas,they interventions to date has focused on conceptual defini- comprise only the most basic of what are characterized as tions and broadly-defined outcome measures,to the the 'Eight Limbs of Yoga,'a cumulative series of stages relative neglect of the program's content and structure, embodying ethical principles of behavior and meditative particularly with respect to Yoga.Kabat-Zinn has written states compiled by the Indian sage Patanjali in a collection extensively about the nature of the original MBSR of aphorism known as sutras (Desikachar,1999).There program (Kabat-Zinn,1996,2003b)and described three are different paths that Yoga practitioners may follow,the key components -sitting meditation,Hatha Yoga,and most widely practiced being Hatha Yoga (physical devel- body scan (a sustained mindfulness practice in which opment);Gnyana Yoga (developing the intellect);Bhakti attention is sequentially directed throughout the body)- Yoga (spiritual devotion);and Karma Yoga (practical at great length.However,little has been written elsewhere action;Patel,1993).The form practiced in the MBSR program,and indeed in most Western healthcare 1077-7229/08/59-72$1.00/0 contexts,is Hatha Yoga. 2008 Association for Behavioral and Cognitive Therapies. The inclusion of Yoga in the MBSR program is Published by Elsevier Ltd.All rights reserved. interesting and warrants detailed consideration.Aside
Yoga and Mindfulness: Clinical Aspects of an Ancient Mind/Body Practice Paul Salmon, Elizabeth Lush, Megan Jablonski, and Sandra E. Sephton Department of Psychological and Brain Sciences, University of Louisville, Louisville, KY 40292 The use of Yoga and other complementary healthcare interventions for both clinical and non-clinical populations has increased substantially in recent years. In this context, we describe the implementation of Hatha Yoga in the Mindfulness-Based Stress Reduction (MBSR) program of Kabat-Zinn and colleagues. This is embedded in a more general consideration of Yoga’s place in complementary healthcare. In providing this overview, we comment on the nature and quality of current research on Yoga, summarize current physiological and psychological explanations of its effects, and discuss practical issues related to teacher training and experience. A. Introduction and Overview There is a long-standing interest in the health benefits of Yoga in India and other non-Western cultures. Yoga is currently experiencing a marked increase in popularity in the West, primarily in health clubs and wellness centers. One program which has advanced the status of Yoga in clinical settings is the mindfulness-based stress reduction (MBSR) program developed by Kabat-Zinn (1990) and colleagues. This work has stimulated extensive clinical practice and research in acceptance-based psychological interventions in recent years (Germer, 2004; Hayes and Feldman, 2004). Outcome studies reviewed elsewhere (Baer, 2003; Salmon, Sephton, Weissbecker, Hoover, Ulmer, & Studts, 2004) attest to its promise as a clinical intervention. A meta-analysis of health benefits associated with MBSR (Grossman, Niemann, Schmidt, & Walach, 2004) reached a similar conclusion, but noted a relative absence of methodologically rigorous studies, and a lack of detail concerning intervention specifics. Indeed, much of the writing about mindfulness interventions to date has focused on conceptual definitions and broadly-defined outcome measures, to the relative neglect of the program’s content and structure, particularly with respect to Yoga. Kabat-Zinn has written extensively about the nature of the original MBSR program (Kabat-Zinn, 1996, 2003b) and described three key components – sitting meditation, Hatha Yoga, and body scan (a sustained mindfulness practice in which attention is sequentially directed throughout the body) – at great length. However, little has been written elsewhere about the implementation of these practices – particularly Yoga – in either clinical or research contexts. Concerning clinical research, studies generally provide little detailed information about specific intervention elements in terms of either content or process factors, and instead focus attention primarily on outcome measures. Yoga as discussed here refers to an integrative physical/ spiritual practice which developed in ancient India. We capitalize the word ‘Yoga’ throughout in recognition of its historical stature as a highly evolved cultural system of beliefs and practices, even though clinical applications tend to ‘de-contextualize’ it from its cultural and spiritual roots. The word ‘Yoga’ means ‘yoke’ or ‘union’ and connotes the interconnection of mind, body, and spirit. Yoga practice in Western contexts involves sequences of postures, called asanas, that incorporate regulated breathing and focused attention. Ongoing practice is reported by practitioners to promote psychological well-being and a variety of physical benefits. Although the focus in Western Yoga practices is usually on the asanas, they comprise only the most basic of what are characterized as the ‘Eight Limbs of Yoga,’ a cumulative series of stages embodying ethical principles of behavior and meditative states compiled by the Indian sage Patanjali in a collection of aphorism known as sutras (Desikachar, 1999). There are different paths that Yoga practitioners may follow, the most widely practiced being Hatha Yoga (physical development); Gnyana Yoga (developing the intellect); Bhakti Yoga (spiritual devotion); and Karma Yoga (practical action; Patel, 1993). The form practiced in the MBSR program, and indeed in most Western healthcare contexts, is Hatha Yoga. The inclusion of Yoga in the MBSR program is interesting and warrants detailed consideration. Aside 1077-7229/08/59–72$1.00/0 © 2008 Association for Behavioral and Cognitive Therapies. Published by Elsevier Ltd. All rights reserved. Available online at www.sciencedirect.com Cognitive and Behavioral Practice 16 (2009) 59–72 www.elsevier.com/locate/cabp
60 Salmon et al. from a mindfulness-based program for depression (Wil- Gong (Ospina et al.,2007).Our intention is to highlight liams,Teasdale,Segal,Kabat-Zinn,2007),Yoga has recent findings from methodologically rigorous studies, received little attention in clinical psychology,despite an which until recently have been relatively few in number. extensive research literature documenting its benefits in As is the case with meditation research as recently noted stress reduction and other contexts (Khalsa,2007).One by Walsh and Shapiro(2006)many studies involving Yoga obvious reason for this omission is that few psychologists as both a lifestyle and clinical practice have been have much experience or training in Yoga and other conducted over the years.Unlike meditation research. physical disciplines.A second possible reason for a lack of however,much of the research on Yoga originated in attention in clinical contexts is that Yoga is associated by Indian research institutes,beginning in the early 20th many more with fitness and health than as a treatment for century.Few of these early studies employed research illness,despite its historical roots in Indian Ayurvedic methodologies now taken for granted,but they did serve medicine. the important function of signaling a new view of Yoga as a Yoga has generated considerable empirical research in form of health and medical care,rather than an other contexts,especially Indian medical practice,which exclusively spiritual practice (Khalsa,2007). we comment on below.Its comparative exclusion from Currently Yoga is among the 10 most widely practiced clinical psychology is something of an anomaly,and this forms of complementary healthcare in the U.S.(Barnes, article is an attempt to rectify this oversight.In discussing Powell-Griner,McFann,Nahin,2004).Yoga practice is the program which he formulated,Kabat-Zinn (1990) linked to demographic variables including gender notes that Yoga was originally included for the practical (female),education level (high),age (post-WWII birth), purpose of helping medical patients overcome disuse and lifestyle (urban;Saper,Eisenberg,Davis,Culpepper, atmophy -deterioration of muscle tissue due to lack of &Phillips,2004).As a result of its growing popularity,Yoga activity-that frequently accompanies illness.In addition, is becoming a focus of increasing clinical research in this however,and perhaps of even greater importance,Yoga country. provides an opportunity to practice mindfulness.Yoga is Results of well-designed recent randomized trials introduced in the program once participants have been employing Yoga as a clinical intervention report promis- exposed to the Body Scan,a physically static exercise in ing results.For example,Yoga has been shown to improve which attention is systematically directed toward internal management of Type II diabetes mellitus (Innes and sensations emanating from different regions of the body, Vincent,2006),relieve chronic low back pain (Sherman, beginning with the feet and progressing to the head.The Cherkin,Erro,Miglioretti,Deyo,2005),improve quality Yoga movement sequences have been formulated with the of life in patients with chronic pancreatitis (Sareen, intention of encouraging mindful awareness:they are Kumari,Gajebasia,Gajebasia,2007),reduce gastro- done slowly and gently and are not overly physically taxing. intestinal symptoms in irritable bowel syndrome(Kuttner, Much of the attention directed at the MBSR program Chambers,Hardial,Israel,Jacobson,Evans,2006),and focuses on sitting meditation,a predominantly cognitive improve the physical capabilities of healthy senior adults practice that has its roots in Buddhist meditation practices. (Oken et al.,2006).A recent article reviewing the impact Hatha Yoga,on the other hand,draws on related but of Yoga interventions on risk factors for chronic disease somewhat distinct cultural and philosophical traditions found evidence that Yoga elicits favorable changes in body that employ physical activity in the context of meditation weight,blood pressure,cholesterol,and blood glucose practice.That the two elements have been juxtaposed in levels (Yang,2007).Studies have also shown that Yoga the same program,along with the body scan,is something interventions are beneficial to emotional wellness,with of an anomaly,reflecting the particular experiences and improvements demonstrated in stress management training of those who originated the program. (Granath,Ingvarsson,von Thiele,Lundberg,2006) and depressive symptoms(Pilkington,Kirkwood,Rampes, B.Clinical Research Richardson,2005).Research studies vary in the degree In recent years,a substantial body of clinical research to which the Yoga practice is described in detail,and it is has accumulated attesting to the health benefits of Yoga.It quite evident from those that provide detailed informa- is not the purpose of this article to review the extant tion that there is considerable variation in how it is research literature;a recent comprehensive analysis of implemented. published studies by Khalsa(2004),and more selective Two recent research studies employing randomized reviews by Innes and Vincent(2006),Innes,Bourgignon, control designs are especially noteworthy in terms of and Taylor (2005),and Raub (2002)do this admirably. methodological rigor and detailed descriptions of the More recently,Yoga is included in an exhaustive review Yoga practice.In one study,38 patients with lymphoma and critique of health-oriented meditation studies invol- were randomly assigned to a seven week Tibetan-based ving mantra and mindfulness meditation,Tai Chi,and Qi Yoga program or a wait-list control group (Cohen
from a mindfulness-based program for depression (Williams, Teasdale, Segal, & Kabat-Zinn, 2007), Yoga has received little attention in clinical psychology, despite an extensive research literature documenting its benefits in stress reduction and other contexts (Khalsa, 2007). One obvious reason for this omission is that few psychologists have much experience or training in Yoga and other physical disciplines. A second possible reason for a lack of attention in clinical contexts is that Yoga is associated by many more with fitness and health than as a treatment for illness, despite its historical roots in Indian Ayurvedic medicine. Yoga has generated considerable empirical research in other contexts, especially Indian medical practice, which we comment on below. Its comparative exclusion from clinical psychology is something of an anomaly, and this article is an attempt to rectify this oversight. In discussing the program which he formulated, Kabat-Zinn (1990) notes that Yoga was originally included for the practical purpose of helping medical patients overcome disuse atrophy – deterioration of muscle tissue due to lack of activity – that frequently accompanies illness. In addition, however, and perhaps of even greater importance, Yoga provides an opportunity to practice mindfulness. Yoga is introduced in the program once participants have been exposed to the Body Scan, a physically static exercise in which attention is systematically directed toward internal sensations emanating from different regions of the body, beginning with the feet and progressing to the head. The Yoga movement sequences have been formulated with the intention of encouraging mindful awareness: they are done slowly and gently and are not overly physically taxing. Much of the attention directed at the MBSR program focuses on sitting meditation, a predominantly cognitive practice that has its roots in Buddhist meditation practices. Hatha Yoga, on the other hand, draws on related but somewhat distinct cultural and philosophical traditions that employ physical activity in the context of meditation practice. That the two elements have been juxtaposed in the same program, along with the body scan, is something of an anomaly, reflecting the particular experiences and training of those who originated the program. B. Clinical Research In recent years, a substantial body of clinical research has accumulated attesting to the health benefits of Yoga. It is not the purpose of this article to review the extant research literature; a recent comprehensive analysis of published studies by Khalsa (2004), and more selective reviews by Innes and Vincent (2006), Innes, Bourgignon, and Taylor (2005), and Raub (2002) do this admirably. More recently, Yoga is included in an exhaustive review and critique of health-oriented meditation studies involving mantra and mindfulness meditation, Tai Chi, and Qi Gong (Ospina et al., 2007). Our intention is to highlight recent findings from methodologically rigorous studies, which until recently have been relatively few in number. As is the case with meditation research as recently noted by Walsh and Shapiro (2006) many studies involving Yoga as both a lifestyle and clinical practice have been conducted over the years. Unlike meditation research, however, much of the research on Yoga originated in Indian research institutes, beginning in the early 20th century. Few of these early studies employed research methodologies now taken for granted, but they did serve the important function of signaling a new view of Yoga as a form of health and medical care, rather than an exclusively spiritual practice (Khalsa, 2007). Currently Yoga is among the 10 most widely practiced forms of complementary healthcare in the U.S. (Barnes, Powell-Griner, McFann, & Nahin, 2004). Yoga practice is linked to demographic variables including gender (female), education level (high), age (post-WWII birth), and lifestyle (urban; Saper, Eisenberg, Davis, Culpepper, & Phillips, 2004). As a result of its growing popularity, Yoga is becoming a focus of increasing clinical research in this country. Results of well-designed recent randomized trials employing Yoga as a clinical intervention report promising results. For example, Yoga has been shown to improve management of Type II diabetes mellitus (Innes and Vincent, 2006), relieve chronic low back pain (Sherman, Cherkin, Erro, Miglioretti, & Deyo, 2005), improve quality of life in patients with chronic pancreatitis (Sareen, Kumari, Gajebasia, & Gajebasia, 2007), reduce gastrointestinal symptoms in irritable bowel syndrome (Kuttner, Chambers, Hardial, Israel, Jacobson, & Evans, 2006), and improve the physical capabilities of healthy senior adults (Oken et al., 2006). A recent article reviewing the impact of Yoga interventions on risk factors for chronic disease found evidence that Yoga elicits favorable changes in body weight, blood pressure, cholesterol, and blood glucose levels (Yang, 2007). Studies have also shown that Yoga interventions are beneficial to emotional wellness, with improvements demonstrated in stress management (Granath, Ingvarsson, von Thiele, & Lundberg, 2006) and depressive symptoms (Pilkington, Kirkwood, Rampes, & Richardson, 2005). Research studies vary in the degree to which the Yoga practice is described in detail, and it is quite evident from those that provide detailed information that there is considerable variation in how it is implemented. Two recent research studies employing randomized control designs are especially noteworthy in terms of methodological rigor and detailed descriptions of the Yoga practice. In one study, 38 patients with lymphoma were randomly assigned to a seven week Tibetan-based Yoga program or a wait-list control group (Cohen, 60 Salmon et al
Yoga and Mindfulness:Clinical Aspects of an Ancient Mind/Body Practice 61 Warneke,Fouladi,Rodriguez.Chaoul-Reich,2004). although voluminous,much of this early research on Yoga The Yoga intervention incorporated regulated breathing was hampered by a range of methodological problems and imagery,mindfulness practice,and sequences of that detract from its empirical foundation and conse- postures (asanas)appropriate for individuals receiving quently limit its clinical utility (Khalsa,2007).For cancer treatment.The sole area of improvement con- example,a recent systematic review by Innes and Vincent cerned sleep quality;changes were noted in depression, (2006)evaluated the methodological rigor of 70 studies anxiety,or fatigue.The significance of this study lies in its published between 1970 and 2004 assessing the effect of robust experimental design,clear description of the Yoga on insulin resistance and cardiovascular disease.In intervention,and demonstration that Yoga can fruitfully terms of experimental design,the majority were observa- be practiced by medical patients receiving taxing treat- tional (1),non-controlled (26),or controlled but non- ment regimens.Yoga was employed in another rando- randomized (21);in contrast,only twenty-two studies mized controlled study (Moadel et al.,2007)involving a (31%)employed a randomized controlled design. multi-ethnic sample of breast cancer patients.The Methodological problems enumerated by these and intervention consisted of twelve weekly 90-minute sessions other authors have included:lack of statistical power, incorporating sequences of poses (asanas),meditation, small sample sizes,substantial variations in Yoga interven- and regulated breathing.This study was especially notable tion protocols,failure to control for possible explanatory for the positive outcomes reported (improved quality of confounds,questionable statistical analyses,and lack of life and emotional well-being,reduced distress),and specificity concerning randomization procedures.They acceptance by ethnically diverse participants. also pointed out that many of these studies were More generally,the therapeutic significance of move- conducted in non-Western clinical research contexts, ment-based interventions including Yoga,Tai Chi,and primarily in India,where Yoga is widely accepted within others was recently emphasized by van der Kolk(2006)in a the prevailing culture.Of the shortcomings noted above, discussion of neuro-cognitive aspects of PTSD.He pre- the most problematic from a research standpoint is the sented compelling evidence that regulation of physical current lack of specificity or standardization with respect movement is a fundamental priority of the nervous system, to the Yoga practice itself.Yang (2007)recently under- perhaps from an evolutionary standpoint even more scored the difficulties inherent in evaluating and replicat- important than regulation of emotional functions.Physical ing interventions without having detailed descriptions of therapies may benefit from'pre-wiring'that augments their the Yoga postures and their sequence,urging the impact on patterns of behavioral reactivity commonly development of a more standardized intervention that associated with various clinical conditions.In addition. could be replicated for research purposes.These meth- physical activity provides a rich source of present-moment odological concerns and contextual factors need to be interoceptive cues that can serve as a focal point for mindful addressed in designing future Yoga-based intervention attention that is comparatively well tolerated by trauma research and clinical practice.In general,the entire field victims,who may otherwise feel overwhelmed by inner of meditation-oriented research is in need of much grea- sensations.Van der Kolk notes however,that aside from ter methodological rigor and consistency (Ospina et al, mindfulness-oriented intervention models such as those of 2007).The fact that a relatively standardized approach to Kabat-Zinn (1990)and Linehan (1993).few Western Yoga practice has already been developed in the MBSR psychological models -even those that ascribe to a program is a promising development in this regard. mind/body perspective -make systematic use of body- centered or movement-based interventions. C.Underlying Physlological Processes The absence of movement therapies in Western Yoga-Hatha Yoga to be specific-involves physical psychotherapy and clinical practice is notable but activity,and in general both physical activity and exercise certainly understandable,given that what Freud termed have been linked to a variety of neurophysiological effects the 'talking cure'has historically placed more emphasis including B-endorphin release and altered brain neuro- on cognitive factors than on physical aspects of transmitter levels,especially dopamine and serotonin, behavior.It also reflects in part the mind/body which have emotion-enhancing effects (Buckworth and dichotomy that has traditionally characterized Western Dishman,2003).However,many of these changes occur health and medical care.In addition,relatively few in the context of relatively high intensity activity,which somatically-based practices have been thoroughly involves heightened activation of the sympathetic nervous empirically validated,despite their broad popularity. system (SNS).In contrast,most forms of Yoga (excluding This is the case,for example,with methods such as high intensity,aerobic variants such as Ashtanga Yoga) those developed by Feldenkrias,Alexander,and Pilates. elicit the 'relaxation response'described by Benson In contrast,Yoga attracted considerable research (1975),a state of physiological de-activation reflecting interest,beginning early in the 20th century.However, dominance of the parasympathetic nervous system(PNS)
Warneke, Fouladi, Rodriguez, & Chaoul-Reich, 2004). The Yoga intervention incorporated regulated breathing and imagery, mindfulness practice, and sequences of postures (asanas) appropriate for individuals receiving cancer treatment. The sole area of improvement concerned sleep quality; changes were noted in depression, anxiety, or fatigue. The significance of this study lies in its robust experimental design, clear description of the intervention, and demonstration that Yoga can fruitfully be practiced by medical patients receiving taxing treatment regimens. Yoga was employed in another randomized controlled study (Moadel et al., 2007) involving a multi-ethnic sample of breast cancer patients. The intervention consisted of twelve weekly 90-minute sessions incorporating sequences of poses (asanas), meditation, and regulated breathing. This study was especially notable for the positive outcomes reported (improved quality of life and emotional well-being, reduced distress), and acceptance by ethnically diverse participants. More generally, the therapeutic significance of movement-based interventions including Yoga, Tai Chi, and others was recently emphasized by van der Kolk (2006) in a discussion of neuro-cognitive aspects of PTSD. He presented compelling evidence that regulation of physical movement is a fundamental priority of the nervous system, perhaps from an evolutionary standpoint even more important than regulation of emotional functions. Physical therapies may benefit from ‘pre-wiring’ that augments their impact on patterns of behavioral reactivity commonly associated with various clinical conditions. In addition, physical activity provides a rich source of present-moment interoceptive cues that can serve as a focal point for mindful attention that is comparatively well tolerated by trauma victims, who may otherwise feel overwhelmed by inner sensations. Van der Kolk notes however, that aside from mindfulness-oriented intervention models such as those of Kabat-Zinn (1990) and Linehan (1993), few Western psychological models – even those that ascribe to a mind/body perspective – make systematic use of bodycentered or movement-based interventions. The absence of movement therapies in Western psychotherapy and clinical practice is notable but certainly understandable, given that what Freud termed the ‘talking cure’ has historically placed more emphasis on cognitive factors than on physical aspects of behavior. It also reflects in part the mind/body dichotomy that has traditionally characterized Western health and medical care. In addition, relatively few somatically-based practices have been thoroughly empirically validated, despite their broad popularity. This is the case, for example, with methods such as those developed by Feldenkrias, Alexander, and Pilates. In contrast, Yoga attracted considerable research interest, beginning early in the 20th century. However, although voluminous, much of this early research on Yoga was hampered by a range of methodological problems that detract from its empirical foundation and consequently limit its clinical utility (Khalsa, 2007). For example, a recent systematic review by Innes and Vincent (2006) evaluated the methodological rigor of 70 studies published between 1970 and 2004 assessing the effect of Yoga on insulin resistance and cardiovascular disease. In terms of experimental design, the majority were observational (1), non-controlled (26), or controlled but nonrandomized (21); in contrast, only twenty-two studies (31%) employed a randomized controlled design. Methodological problems enumerated by these and other authors have included: lack of statistical power, small sample sizes, substantial variations in Yoga intervention protocols, failure to control for possible explanatory confounds, questionable statistical analyses, and lack of specificity concerning randomization procedures. They also pointed out that many of these studies were conducted in non-Western clinical research contexts, primarily in India, where Yoga is widely accepted within the prevailing culture. Of the shortcomings noted above, the most problematic from a research standpoint is the current lack of specificity or standardization with respect to the Yoga practice itself. Yang (2007) recently underscored the difficulties inherent in evaluating and replicating interventions without having detailed descriptions of the Yoga postures and their sequence, urging the development of a more standardized intervention that could be replicated for research purposes. These methodological concerns and contextual factors need to be addressed in designing future Yoga-based intervention research and clinical practice. In general, the entire field of meditation-oriented research is in need of much greater methodological rigor and consistency (Ospina et al, 2007). The fact that a relatively standardized approach to Yoga practice has already been developed in the MBSR program is a promising development in this regard. C. Underlying Physiological Processes Yoga – Hatha Yoga to be specific – involves physical activity, and in general both physical activity and exercise have been linked to a variety of neurophysiological effects including β-endorphin release and altered brain neurotransmitter levels, especially dopamine and serotonin, which have emotion-enhancing effects (Buckworth and Dishman, 2003). However, many of these changes occur in the context of relatively high intensity activity, which involves heightened activation of the sympathetic nervous system (SNS). In contrast, most forms of Yoga (excluding high intensity, aerobic variants such as Ashtanga Yoga) elicit the ‘relaxation response’ described by Benson (1975), a state of physiological de-activation reflecting dominance of the parasympathetic nervous system (PNS). Yoga and Mindfulness: Clinical Aspects of an Ancient Mind/Body Practice 61
62 Salmon et al. Yoga is commonly practiced in a focused,yet relaxed respiration and neuromuscular function:and altered manner.It shares in common with meditative/contem- cognitive and neurophysiological status.It is also possible plative practices an emphasis on focused attention, that Yoga has direct beneficial effects on health that are reduced extraneous external stimulation,controlled mediated through other pathways related to neurological breathing,and relaxation;thus,it has much in common approach rather than avoidance (stress)mechanisms.It with stress reduction practices eliciting the relaxation may be fruitful for research to explore effects of Yoga on response.Such practices have been found to have serotonergic,dopaminergic,and endogenous opioid measurable effects on brain function assessed by imaging pathways. techniques (Lazar,Bush,Gollub,Fricchione,Khalsa, The physiological effects of relaxation have been Benson,2000),attention-related cognitive processing thoroughly documented in broad-based,clinical research, (Galvin,Benson,Deckro,Fricchione,Dusek,2006) beginning with the work of Benson (1975).However, and cardiorespiratory function (Danucalov,Simoes, comparatively few recent studies have examined the Kozasa,Leite,2008;Dusek et al.,2006),although the physiological effects of Yoga practice per se,and more strength of such effects varies depending on the specific methodologically rigorous studies are needed.Among the practice (Peng et al.,2004).A growing body of research handful of studies that have been conducted,one study of on biological and psychological correlates of movement is 35 male volunteers showed that heart rate and skin revealing new ways in which simple behavior patterns,for conductance decreased after a guided relaxation based example walking,interact reciprocally with cognitive and on Yoga (Vempati and Telles,2002),and another emotional states(Acevdeo and Ekkekakis,2006).Walking, demonstrated reductions in heart rate and blood pressure Yoga,and other repetitive motion patterns appear to among Type II diabetics after 40 days (Singh,Malhotra, restore and entrain the rhythmicity of biological functions Singh,Madhu,Tandon,2004).Benefits in autonomic that are often disrupted during periods of stress. function have been noted among samples of refractory A two-part physiological model has recently been epilepsy patients (increased parasympathetic function; proposed (Innes,Bourguignon,Taylor,2005)to Sathyaprabha et al.,2007)and in Type II diabetic patients account for the relaxation-inducing effects of Yoga.First, (reduced allostatic load parameters of glycemic load and it may help balance the reactivity of endocrine stress cardiac activity;Singh,Malhotra,Singh,Madhu, responses,perhaps ameliorating hyper-or hypoactivation Tandon,2004).To the extent that Yoga is linked to of the SNS and the hypothalamic-pituitary-adrenal(HPA) attention-focusing mindfulness,it is likely to reduce axis.Frequent stress-related activation and/or chronic sympathetic over-activation associated with PTSD symp- suppression of the SNS and HPA results in altered toms.Yoga may also be effective in reducing physiological catecholamine (epinephrine and norepinephrine)and symptoms of PTSD,particularly when pronounced cortisol secretion.Both SNS and HPA activation are autonomic hyperarousal is involved either directly associated with heightened arousal and reactivity states (Gupta,Lanius,Van der Kolk,2005),or in the context that are normally balanced by parasympathetic activation, of attention-focusing mindfulness (van der Kolk,2006). which exerts a restorative,energy-conservative effect. Despite these promising findings,more research on the Chronic stress may lead to imbalances in stress-related effects of Yoga on autonomic balance,HPA,metabolic, versus restorative neural responses,with damaging effects neuromuscular and neurocognitive functions is needed on other body systems including regulatory mechanisms before its specific effects can fully understood. (McEwen,1997;McEwen Lasley,2003:McEwen Seeman,1999).Yoga may curtail chronic stress-related D.Clinical Implementation activation,and potentially reduce allostatic load,the One of the most obvious challenges facing greater cumulative impact of chronic HPA and SNS activation acceptance of Yoga within mainstream Western health- (McEwen.1997). care has to do with its cultural,spiritual and social origins The second part of the hypothesis suggests that Yoga in India,where it flourished for centuries without the level enhances PNS activation through relaxation-inducing slow of empirical validation and scientific verification required movement patterns that reduce heart rate and blood for widespread acceptance in contemporary biomedical pressure via stimulation of the vagus nerve,which settings.As is the case with meditation,another connects cardiac control centers located in the brain 'imported'complementary health care practice,Yoga stem with the heart's intrinsic pacemaker,the sino-atrial has in recent years been transplanted into Western node (Powers and Howley,2006).In addition to altered culture and healthcare,where the enthusiasm of its autonomic and HPA function,Khalsa (2007)recently practitioners has been countered by the skepticism of the highlighted additional physiological mechanisms by biomedical community due to the lack of strong valida- which Yoga may exert its effects.These include:reduced tion data.Validation studies are needed oriented toward metabolic rate and lower oxygen consumption;improved the pragmatics of Western healthcare that value
Yoga is commonly practiced in a focused, yet relaxed manner. It shares in common with meditative/contemplative practices an emphasis on focused attention, reduced extraneous external stimulation, controlled breathing, and relaxation; thus, it has much in common with stress reduction practices eliciting the relaxation response. Such practices have been found to have measurable effects on brain function assessed by imaging techniques (Lazar, Bush, Gollub, Fricchione, Khalsa, & Benson, 2000), attention-related cognitive processing (Galvin, Benson, Deckro, Fricchione, & Dusek, 2006) and cardiorespiratory function (Danucalov, Simoes, Kozasa, & Leite, 2008; Dusek et al., 2006), although the strength of such effects varies depending on the specific practice (Peng et al., 2004). A growing body of research on biological and psychological correlates of movement is revealing new ways in which simple behavior patterns, for example walking, interact reciprocally with cognitive and emotional states (Acevdeo and Ekkekakis, 2006). Walking, Yoga, and other repetitive motion patterns appear to restore and entrain the rhythmicity of biological functions that are often disrupted during periods of stress. A two-part physiological model has recently been proposed (Innes, Bourguignon, & Taylor, 2005) to account for the relaxation-inducing effects of Yoga. First, it may help balance the reactivity of endocrine stress responses, perhaps ameliorating hyper- or hypoactivation of the SNS and the hypothalamic-pituitary-adrenal (HPA) axis. Frequent stress-related activation and/or chronic suppression of the SNS and HPA results in altered catecholamine (epinephrine and norepinephrine) and cortisol secretion. Both SNS and HPA activation are associated with heightened arousal and reactivity states that are normally balanced by parasympathetic activation, which exerts a restorative, energy-conservative effect. Chronic stress may lead to imbalances in stress-related versus restorative neural responses, with damaging effects on other body systems including regulatory mechanisms (McEwen, 1997; McEwen & Lasley, 2003; McEwen & Seeman, 1999). Yoga may curtail chronic stress-related activation, and potentially reduce allostatic load, the cumulative impact of chronic HPA and SNS activation (McEwen, 1997). The second part of the hypothesis suggests that Yoga enhances PNS activation through relaxation-inducing slow movement patterns that reduce heart rate and blood pressure via stimulation of the vagus nerve, which connects cardiac control centers located in the brain stem with the heart’s intrinsic pacemaker, the sino-atrial node (Powers and Howley, 2006). In addition to altered autonomic and HPA function, Khalsa (2007) recently highlighted additional physiological mechanisms by which Yoga may exert its effects. These include: reduced metabolic rate and lower oxygen consumption; improved respiration and neuromuscular function; and altered cognitive and neurophysiological status. It is also possible that Yoga has direct beneficial effects on health that are mediated through other pathways related to neurological approach rather than avoidance (stress) mechanisms. It may be fruitful for research to explore effects of Yoga on serotonergic, dopaminergic, and endogenous opioid pathways. The physiological effects of relaxation have been thoroughly documented in broad-based, clinical research, beginning with the work of Benson (1975). However, comparatively few recent studies have examined the physiological effects of Yoga practice per se, and more methodologically rigorous studies are needed. Among the handful of studies that have been conducted, one study of 35 male volunteers showed that heart rate and skin conductance decreased after a guided relaxation based on Yoga (Vempati and Telles, 2002), and another demonstrated reductions in heart rate and blood pressure among Type II diabetics after 40 days (Singh, Malhotra, Singh, Madhu, & Tandon, 2004). Benefits in autonomic function have been noted among samples of refractory epilepsy patients (increased parasympathetic function; Sathyaprabha et al., 2007) and in Type II diabetic patients (reduced allostatic load parameters of glycemic load and cardiac activity; Singh, Malhotra, Singh, Madhu, & Tandon, 2004). To the extent that Yoga is linked to attention-focusing mindfulness, it is likely to reduce sympathetic over-activation associated with PTSD symptoms. Yoga may also be effective in reducing physiological symptoms of PTSD, particularly when pronounced autonomic hyperarousal is involved either directly (Gupta, Lanius, & Van der Kolk, 2005), or in the context of attention-focusing mindfulness (van der Kolk, 2006). Despite these promising findings, more research on the effects of Yoga on autonomic balance, HPA, metabolic, neuromuscular and neurocognitive functions is needed before its specific effects can fully understood. D. Clinical Implementation One of the most obvious challenges facing greater acceptance of Yoga within mainstream Western healthcare has to do with its cultural, spiritual and social origins in India, where it flourished for centuries without the level of empirical validation and scientific verification required for widespread acceptance in contemporary biomedical settings. As is the case with meditation, another ‘imported’ complementary health care practice, Yoga has in recent years been transplanted into Western culture and healthcare, where the enthusiasm of its practitioners has been countered by the skepticism of the biomedical community due to the lack of strong validation data. Validation studies are needed oriented toward the pragmatics of Western healthcare that value 62 Salmon et al
Yoga and Mindfulness:Clinical Aspects of an Ancient Mind/Body Practice 63 interventions primarily to the extent that they reduce practices that form the core of the MSBR program,along pain and suffering associated with illness.Clearly,there is with sitting meditation and the body scan.Each of these a need to develop more systematic means of specifying practices,described in greater detail below,is taught the nature of Yoga-based interventions in clinical research during program sessions and then done at home using and practice.This is especially important owing to the narratives on tape or CD for guidance.To date,more than popularity of Yoga and the degree to which it is making 15,000 patients and participants from a variety of referral significant inroads into clinical healthcare.Establishing sources have taken the program.The evolution of a research guidelines for study design,intervention speci- consistent sequence of asanas in the MBSR program, fication,and teacher training are among the most practiced by thousands of medical patients,provides a pressing needs,all of which would contribute substantially relatively standardized,field-tested intervention that is to controlling confounding variables that detract from the worth consideration by anyone contemplating research rigor of most extant research.Complete and accurate on the clinical benefits of Hatha Yoga. intervention descriptions could allow researchers to further uphold the standards necessary for maintaining E.MBSR-based Yoga accuracy,reporting and corroborating results across In the context of the MBSR program,Yoga provides a studies.Providing the critical information necessary for means of practicing 'mindfulness in motion.'Practically accurate replication and implementing stricter protocol speaking,it also addresses the problem of'disuse atrophy' control across clinical trials may further substantiate the common in medical patients as a result of reduced physical use of Yoga as a treatment option among clinical activity.The structure and underlying philosophy of the populations.In this context,it is important to be able to MBSR program are described in detail by Kabat-Zinn evaluate both positive and negative outcomes and other (1990).The basic premise underlying mindfulness practice manifestations of individual differences. is that living 'in the present'can be an effective antidote to To date,there does not appear to be widespread the myriad stressors people experience as a result of agreement in this regard.There are several possible cognitively-based projections into the past or future often reasons for this.First,the term Yoga'encompasses many marked by regret,fear,or apprehension.The Yoga practice different forms of practice,of which perhaps the most consists of two separate sequences of asanas,performed in a widely practiced is Hatha Yoga,which as noted emphasizes state of focused,yet relaxed,awareness.Each sequence lasts physical development.But even within the domain of approximately 45 minutes,and is practiced using an Hatha Yoga there are variations,including Bikram, accompanying audio tape/CD for guidance.Participants lyengar,and Ashtanga Yoga.Second,Yoga has been are expected to devote between 45 and 60 minutes most implemented primarily in private studios and health clubs days of the week to various combinations of Yoga,the Body which do not share in common standards of practice. Scan and Sitting Meditation. Third,virtually all schools of Yoga emphasize the A recent study by Carmody and Baer (2008)attests to importance of individualized instruction and personal the impact of this component of the MBSR program. adaptation,a perspective that runs somewhat counter to These authors reported results from a large (n =172) the idea of standardization.An exception to this is Bikram within-subjects MBSR trial conducted among patients Yoga,which consists of an invariant sequence of asanas with varied medical conditions at the University of that has been patented by its founder,and which is taught Massachusetts Medical School.Because they carefully by certified teachers specifically trained to conduct the gathered patient home practice logs and assessed mind- classes.A practical problem with Bikram Yoga,however,is fulness skills before and after the intervention,the that it is taught in a very hot environment that limits its authors were able to document the importance of home application,especially with respect to medical patients.In practice in cultivating mindfulness skills and the con- addition,several of the poses themselves are quite sequent decrease in psychological symptoms.Signifi- challenging from a physical standpoint,and not well cantly,the Yoga practice (vs.Body Scan and Sitting suited to beginning practitioners unless they are carefully Meditation)was clearly most strongly associated with and individually supervised. improvements in psychological well-being,and reduction The MBSR-based Yoga sequences comprise one of the of both perceived stress and psychological symptoms.It is few relatively replicable models in this regard.Hatha Yoga especially noteworthy that Yoga-involving movement is practiced as part of an eight-week meditation-based and physical activity -was most effective in reducing program comprised of weekly 2.5-hour sessions con- psychological symptoms,a finding consistent with a ducted in a group format.Historically,most participants previous study by Kabat-Zinn,Chapman-Waldrop,and were referred to the program by physicians at the medical Salmon (1997). center,but self-referrals have increased significantly in Given the apparent impact of Yoga on MBSR out- recent years.As already noted,Yoga is one of three comes,a more detailed analysis of this aspect of the
interventions primarily to the extent that they reduce pain and suffering associated with illness. Clearly, there is a need to develop more systematic means of specifying the nature of Yoga-based interventions in clinical research and practice. This is especially important owing to the popularity of Yoga and the degree to which it is making significant inroads into clinical healthcare. Establishing research guidelines for study design, intervention specification, and teacher training are among the most pressing needs, all of which would contribute substantially to controlling confounding variables that detract from the rigor of most extant research. Complete and accurate intervention descriptions could allow researchers to further uphold the standards necessary for maintaining accuracy, reporting and corroborating results across studies. Providing the critical information necessary for accurate replication and implementing stricter protocol control across clinical trials may further substantiate the use of Yoga as a treatment option among clinical populations. In this context, it is important to be able to evaluate both positive and negative outcomes and other manifestations of individual differences. To date, there does not appear to be widespread agreement in this regard. There are several possible reasons for this. First, the term 'Yoga' encompasses many different forms of practice, of which perhaps the most widely practiced is Hatha Yoga, which as noted emphasizes physical development. But even within the domain of Hatha Yoga there are variations, including Bikram, Iyengar, and Ashtanga Yoga. Second, Yoga has been implemented primarily in private studios and health clubs which do not share in common standards of practice. Third, virtually all schools of Yoga emphasize the importance of individualized instruction and personal adaptation, a perspective that runs somewhat counter to the idea of standardization. An exception to this is Bikram Yoga, which consists of an invariant sequence of asanas that has been patented by its founder, and which is taught by certified teachers specifically trained to conduct the classes. A practical problem with Bikram Yoga, however, is that it is taught in a very hot environment that limits its application, especially with respect to medical patients. In addition, several of the poses themselves are quite challenging from a physical standpoint, and not well suited to beginning practitioners unless they are carefully and individually supervised. The MBSR-based Yoga sequences comprise one of the few relatively replicable models in this regard. Hatha Yoga is practiced as part of an eight-week meditation-based program comprised of weekly 2.5-hour sessions conducted in a group format. Historically, most participants were referred to the program by physicians at the medical center, but self-referrals have increased significantly in recent years. As already noted, Yoga is one of three practices that form the core of the MSBR program, along with sitting meditation and the body scan. Each of these practices, described in greater detail below, is taught during program sessions and then done at home using narratives on tape or CD for guidance. To date, more than 15,000 patients and participants from a variety of referral sources have taken the program. The evolution of a consistent sequence of asanas in the MBSR program, practiced by thousands of medical patients, provides a relatively standardized, field-tested intervention that is worth consideration by anyone contemplating research on the clinical benefits of Hatha Yoga. E. MBSR-based Yoga In the context of the MBSR program, Yoga provides a means of practicing 'mindfulness in motion.' Practically speaking, it also addresses the problem of ‘disuse atrophy’ common in medical patients as a result of reduced physical activity. The structure and underlying philosophy of the MBSR program are described in detail by Kabat-Zinn (1990). The basic premise underlying mindfulness practice is that living 'in the present' can be an effective antidote to the myriad stressors people experience as a result of cognitively-based projections into the past or future often marked by regret, fear, or apprehension. The Yoga practice consists of two separate sequences of asanas, performed in a state of focused, yet relaxed, awareness. Each sequence lasts approximately 45 minutes, and is practiced using an accompanying audio tape/CD for guidance. Participants are expected to devote between 45 and 60 minutes most days of the week to various combinations of Yoga, the Body Scan and Sitting Meditation. A recent study by Carmody and Baer (2008) attests to the impact of this component of the MBSR program. These authors reported results from a large (n = 172) within-subjects MBSR trial conducted among patients with varied medical conditions at the University of Massachusetts Medical School. Because they carefully gathered patient home practice logs and assessed mindfulness skills before and after the intervention, the authors were able to document the importance of home practice in cultivating mindfulness skills and the consequent decrease in psychological symptoms. Significantly, the Yoga practice (vs. Body Scan and Sitting Meditation) was clearly most strongly associated with improvements in psychological well-being, and reduction of both perceived stress and psychological symptoms. It is especially noteworthy that Yoga – involving movement and physical activity – was most effective in reducing psychological symptoms, a finding consistent with a previous study by Kabat-Zinn, Chapman-Waldrop, and Salmon (1997). Given the apparent impact of Yoga on MBSR outcomes, a more detailed analysis of this aspect of the Yoga and Mindfulness: Clinical Aspects of an Ancient Mind/Body Practice 63