Kristen E. Riley

How does yoga reduce stress? A systematic review of mechanisms of change and guide to future inquiry

Yoga is increasingly used in clinical settings for a variety of mental and physical health issues, particularly stress-related illnesses and concerns, and has demonstrated promising efficacy. Yet the ways in which yoga reduces stress remain poorly understood. To examine the empirical evidence regarding the mechanisms through which yoga reduces stress, we conducted a systematic review of the literature, including any yoga intervention that measured stress as a primary dependent variable and tested a mechanism of the relationship with mediation. Our electronic database search yielded 926 abstracts, of which 71 were chosen for further inspection and 5 were selected for the final systematic review. These five studies examined three psychological mechanisms (positive affect, mindfulness and self-compassion) and four biological mechanisms (posterior hypothalamus, interleukin-6, C-reactive protein and cortisol). Positive affect, self-compassion, inhibition of the posterior hypothalamus and salivary cortisol were all shown to mediate the relationship between yoga and stress. It is striking that the literature describing potential mechanisms is growing rapidly, yet only seven mechanisms have been empirically examined; more research is necessary. Also, future research ought to include more rigorous methodology, including sufficient power, study randomisation and appropriate control groups.

Mindfulness-based stress reduction for people living with HIV/AIDS: preliminary review of intervention trial methodologies and findings.

In the context of successful antiretroviral therapy (ART) for the management of HIV infection, the harmful effects of stress remain a significant threat. Stress may increase viral replication, suppress immune response, and impede adherence to ART. Stressful living conditions of poverty, facing a chronic life-threatening illness and stigma all exacerbate chronic stress in HIV-affected populations. Stress-reduction interventions are urgently needed for the comprehensive care of people living with HIV. Mindfulness-based stress reduction (MBSR) is one approach that has shown promise as an intervention for patients facing other medical conditions for reducing disease progression, psychological distress and maladaptive behaviours. In this systematic review, we identified 11 studies that have examined MBSR as an intervention for HIV-positive populations. Of the studies, six were randomised designs, one was a quasi-experimental design, and the remaining four were pre- and post-test designs. The preliminary outcomes support MBSR to decrease emotional distress with mixed evidence for impact on disease progression. Effect sizes were generally small to moderate in magnitude. The early findings from this emerging literature must be considered preliminary and support moving forward with more rigorous controlled trials, evaluated with objective assessments in longer-term follow-ups to determine the efficacy of MBSR for people living with HIV.

A Systematic Scoping Review of Yoga Intervention Components and Study Quality

CONTEXT The scientific study of yoga requires rigorous methodology. This review aimed to systematically assess all studies of yoga interventions to (1) determine yoga intervention characteristics; (2) examine methodologic quality of the subset of RCTs; and (3) explore how well these interventions are reported. EVIDENCE ACQUISITION Searches were conducted through April 2012 in PubMed, PsycINFO, Ageline, and Ovids Alternative and Complementary Medicine database using the text term yoga, and through handsearching five journals. Original studies were included if the intervention (1) consisted of at least one yoga session with some type of health assessment; (2) targeted adults aged ≥18 years; (3) was published in an English-language peer-reviewed journal; and (4) was available for review. EVIDENCE SYNTHESIS Of 3,062 studies identified, 465 studies in 30 countries were included. Analyses were conducted through 2013. Most interventions took place in India (n=228) or the U.S. (n=124), with intensity ranging from a single yoga session up to two sessions per day. Intervention lengths ranged from one session to 2 years. Asanas (poses) were mentioned as yoga components in 369 (79%) interventions, but were either minimally or not at all described in 200 (54%) of these. Most interventions (74%, n=336) did not include home practice. Of the included studies, 151 were RCTs. RCT quality was rated as poor. CONCLUSIONS This review highlights the inadequate reporting and methodologic limitations of current yoga intervention research, which limits study interpretation and comparability. Recommendations for future methodology and reporting are discussed.

Meaning making coping, making sense, and post-traumatic growth following the 9/11 terrorist attacks

According to the meaning making model, traumatic events disrupt global meaning systems, and meaning making coping helps restore congruency between global meaning and appraisals of traumatic events. We examined the contextual and coping predictors of two specific meanings made: having made sense and perceiving post-traumatic growth in a nationally representative sample of 1004 adults approximately six weeks after the September 11th terrorist attacks in the United States. Although the two meanings made were positively correlated, they had very different predictors: having made sense was primarily predicted by some aspects of meaning focused coping as well as other typically adaptive coping (e.g., active coping), but perceived growth was predicted by nearly all types of coping. Further, having made sense was related to less distress, but perceived growth was related to more distress. These results suggest that having made sense is a product of meaning focused and active coping and appears adaptive, while post-traumatic growth reflects a mix of positive functioning and continued distress and coping efforts.

Why practice yoga? Practitioners’ motivations for adopting and maintaining yoga practice

We examined motives for adopting and maintaining yoga practice in a national survey of yoga practitioners (360 yoga students, 156 yoga teachers). Both students and teachers adopted yoga practice primarily for exercise and stress relief, but reported many other reasons, including flexibility, getting into shape, and depression/anxiety relief. Over 62 percent of students and 85 percent of teachers reported having changed their primary reason for practicing or discovering other reasons; for both, the top changed primary reason was spirituality. Findings suggest that most initiate yoga practice for exercise and stress relief, but for many, spirituality becomes their primary reason for maintaining practice.

Comparison groups in yoga research: A systematic review and critical evaluation of the literature

OBJECTIVES Comparison groups are essential for accurate testing and interpretation of yoga intervention trials. However, selecting proper comparison groups is difficult because yoga comprises a very heterogeneous set of practices and its mechanisms of effect have not been conclusively established. METHODS We conducted a systematic review of the control and comparison groups used in published randomized controlled trials (RCTs) of yoga. RESULTS We located 128 RCTs that met our inclusion criteria; of these, 65 included only a passive control and 63 included at least one active comparison group. Primary comparison groups were physical exercise (43%), relaxation/meditation (20%), and education (16%). Studies rarely provided a strong rationale for choice of comparison. Considering year of publication, the use of active controls in yoga research appears to be slowly increasing over time. CONCLUSIONS Given that yoga has been established as a potentially powerful intervention, future research should use active control groups. Further, care is needed to select comparison conditions that help to isolate the specific mechanisms of yogas effects.

The Essential Properties of Yoga Questionnaire: Development and Methods.

Yoga interventions have considerable heterogeneity, are multi-dimensional, and may impact health in different ways. However, most research reports regarding the effects of yoga on health and wellbeing do not adequately describe the components of the yoga interventions being used. Thus, drawing comparisons across studies or understanding the relative effects of specific aspects of a yoga intervention are rarely possible. To address this problem, we created the Essential Properties of Yoga Questionnaire (EPYQ) Project, an NCCAM-funded set of studies to develop a translational tool for yoga researchers. Here we describe the methods and developmental processes used in the EPYQ Project in detail. The project consists of four main phases. Phase I was designed to gain a comprehensive understanding of the relevant aspects of yoga by conducting a comprehensive systematic literature review and conducting focus groups with stakeholders including a wide variety of yoga teachers and students. In Phase II, a pool of potential questionnaire items was developed for the prototypic questionnaire using information from Phase I. Cognitive interviews were conducted with the preliminary EPYQ items to assess the perceived clarity, meaning, and importance of each item. In Phase III, the prototypic questionnaire was administered to two large samples of yoga students and instructors. Military personnel and veterans who practiced or taught yoga (n = 329) were recruited to participate. Factor analysis and item response theory were used to identify factors and select the final questionnaire items. Phase IV is ongoing and will collect reliability and validity data on the final instrument. Results are expected to be available in 2016. The EPYQ will provide an objective tool for describing the amount of various components of yoga interventions, eventually allowing researchers to link specific yoga components to health benefits, and facilitating the design of yoga interventions for specific health conditions.

Improving physical and mental health in frontline mental health care providers: Yoga-based stress management versus cognitive behavioral stress management

ABSTRACT The need for brief, low-cost, easily disseminable, and effective interventions to promote healthy lifestyles is high. This is especially true for mental health providers. The authors developed two studies to compare the impacts of Cognitive Behavioral Stress Management (CBSM) and Yoga-Based Stress Management (YBSM) interventions for health care professionals. Study 1 offered an 8-week YBSM intervention to 37 mental health care participants and collected health data pre- and post. Study 2 offered YBSM and CBSM classes to 40 randomly assigned mental health care providers and collected mental and physical health data at four time points. In Study 1, using t tests, the YBSM intervention affected a number of mental and physical well-being indices pre to post. In Study 2, using linear mixed modeling, YBSM and CBSM groups both improved significantly (p < .05) in fruit and vegetable intake, heart rate, alcohol consumption, relaxation and awareness, professional quality of life, compassion satisfaction, burnout, depression, and stress levels. There was a group by time effect for coping confidence (CBSM increased more, p < .05, F = 4.34), physical activity (YBSM increased more, p < .05, F = 3.47), overall mental health (YBSM increased more, p < .10, F = 5.32), and secondary traumatic stress (YBSM decreased more, p < .10, F = 4.89). YBSM and CBSM appear to be useful for health care professionals’ mental and physical health. YBSM demonstrates some benefit above and beyond the extremely well studied and empirically supported CBSM, including increased physical activity, overall mental health, and decreased secondary traumatic stress benefits.

Assessing Disruptions in Meaning: Development of the Global Meaning Violation Scale

Models of meaning making following stressful events are based on the notion that individuals’ appraisals of events (i.e., their situational meaning) can violate their goals and beliefs (i.e., global meaning), and that resulting discrepancies between situational meaning and global meaning negatively affect their psychological adjustment. To date, research has relied primarily on indirect measures of meaning violation. We describe the development of a new instrument, the Global Meaning Violation Scale (GMVS), for directly assessing belief and goal violations. We establish the psychometric integrity of the GMVS across three studies. In Study 1, we identify and replicate a factor structure consisting of three subscales: belief violation, intrinsic goal violation, and extrinsic goal violation. In Study 2, we provide evidence for the reliability and validity of the GMVS. In Study 3, we test the predictive validity of the GMVS in a sample of undergraduates reporting on the most stressful experiences of their lives. Our findings indicate that the GMVS is a reliable and valid tool for directly examining global meaning violation. We anticipate that the GMVS will advance research on stress, trauma, and coping by giving researchers a tool to directly explore the role of violations in meaning making processes.

P04.76. Characteristics of yoga practice in an undergraduate student sample

Purpose Young adults are increasingly practicing yoga (Barnes et al., 2008) and yoga interventions have been shown to decrease stress and anxiety. However, little is known about the characteristics of young adults who engage in yoga or the correlates of yoga practice outside of clinical contexts. Our objective was to characterize students who practice yoga and to examine correlates of recent yoga practice.