Interested in the science behind yoga, but intimidated by the full scientific publications?

Websites   

• National Center for Complementary and Alternative Medicine:  NCCAM is a part of the National Institute of Health (NIH).  Its purpose is to scientifically investigate complementary and alternative medicine healing practices.   This website describes yoga as defined by the NCCAM and provides other general information and research spotlights on yoga.
• Yoga Health Foundation: This nonprofit organization aims to increase awareness of the health benefits of yoga, provides online resources, and coordinates national awareness campaigns (National Yoga Month and Yoga Recess-In-Schools).
• International Association of Yoga Therapists: IAYT supports research and education in Yoga, and serves as a professional organization for Yoga teachers and Yoga therapists worldwide.

TED Talks and Other Videos

• Jill Bolte Taylor’s Stroke of Insight: Discusses experiencing nirvana as she lost connection with her left hemisphere during a stroke.

• Matthieu Ricard’s The Habits of Happiness: Discusses how we can train our mind to be happy regardless of our circumstances.

• Mihaly Czikszentmihalyi’s Flow, the Secret to Happiness: Discusses what being in flow feels like and how it increases happiness.

• Carl Honore’s In Praise of Slowness: Discusses the importance of slowing down and viewing time in a more cyclical, rather than linear way.

• Brené Brown’s Listening to Shame: Discusses what can happen when people confront their shame.
• Andy Puddicombe’s All It Takes is 10 Mindful Minutes: Discusses the power of refreshing your mind for ten minutes a day by being in the present moment.
• Amy Cuddy’s Your Body Language Shapes Who You Are: Discusses how different poses affect our brain, how others see us, and how we see ourselves.
• The Science of Happiness- An Experiment In Gratitude: Demonstrates how gratitude affects mood.
• Unraveling the Science Behind Yoga’s Benefits– An interview of Gabriel Axel (Yoga Teacher/Neuroscientist), Dr. John Denninger (Director of Research at Benson-Henry Institute for Mind Body Medicine), and Dr. Sat Bir Khalsa (Assistant Professor of Medicine at Harvard Medical School): Discusses the body’s connection to the brain during yoga.

Research

Light Read

• Psychotherapy Goes from Couch to Yoga Mat:  This article discusses the integration of yoga into psychotherapy and the relationship between them.
• Relax! Yoga helps the heart, research at KU Hospital says: This article reviews research done at the University of Kansas Hospital which found that practicing yoga has benefits for patients with atrial fibrillation.

• Yoga May Help Mental Health Disorders, from Depression to Schizophrenia: This article discusses a recent review study done by researchers at Duke University, which found yoga was linked to improvement for depression, schizophrenia, ADHD, and sleep problems.  The authors mention that more research in this area is needed to fully understand the promise of yoga for enhancing mental health. To read the full research paper, scroll down and click on “Frontiers in Psychiatry”, or click here.
• Yoga as a Practice Tool: “With a growing body of research supporting yoga’s mental health benefits, psychologists are weaving the practice into their work with clients.” This article discusses what several researchers, professors, and psychologists have to say about the integration of yoga into psychology.

• Scientific Basis For Yoga Benefits: This is a review of a study that found yoga may lower an inflammatory protein that is linked with stress and aging.  Speculations are made as to how yoga may help reduce stress and reduce risk for age-related diseases.

• Yoga for Anxiety and Depression:  This article reviews previous yoga studies that examined the effects of yoga on psychological and physiological health.
• Teaching Kids Mindfulness Improves their Attention: This article discusses a recent study that showed a brief mindfulness training had benefits for children.
• Your Brain on OM- The Science of Mantra: This articles discusses how mantras resonate in different areas of our mind and body.
• The Science of Posture: This blog post discusses how posture affects our well-being.

In-Depth Read

• Insular Cortex Mediates Increased Pain Tolerance in Yoga Practitioners: This study, published in 2013, examined pain tolerance and neuroanatomical differences between experienced yogis and controls. Findings included that yogis were more tolerant of pain, yogis had higher intrainsular connectivity, and some enhancements of the insula were related to higher pain tolerance. The researchers suggest that the insular cortex, which plays a role in regulating the body’s homeostasis, mediates increased pain tolerance in those who practice yoga.

• Yoga for Depression: A Systematic Review and Meta-Analysis: This study, published in 2013, is the first meta-analysis on yoga for depression. The purpose of this research was to review the effectiveness of different yoga interventions on depression severity in patients with depressive disorder and elevated levels of depression. The review found some evidence for short-term effects of yoga compared to usual care on depression severity. Limited evidence was found for effects of yoga on depression severity compared to relaxation and other exercise. Overall, there was some evidence that short-term yoga interventions improved depression severity and anxiety symptoms. Although this review has various methodological limitations, the research suggests that yoga could be a supplemental treatment for patients with depression.

• Effects of Yoga on Psychological Health, Quality of Life, and Physical Health of Patients with Cancer: A Meta-Analysis: This study was published in 2011 in Evidence-Based Complementary and Alternative Medicine.  It reviews previous studies that explore the effects of yoga  in patients with cancer.  The preliminary findings show that those in the yoga group experienced greater improvements in psychological health. Click on “Full-Text PDF” in the upper right hand corner to see the full research article.

• Stress, Inflammation, and Yoga Practice: The purpose of this research was to examine the effects of yoga, slow walking, and passive activity on cardiovascular, inflammatory, and endocrine responses, and physiologic responses to stress in women who were both yoga novices and experts. The results suggest that a regular yoga practice could have important health benefits over time.

• Rapid Gene Expression Changes in Peripheral Blood Lymphocytes Upon Practice of a Comprehensive Yoga Program: This study examined the immediate effects of practicing yoga on gene expression profiles in peripheral blood lymphocytes. While the study is limited by a small sample size, the findings are intriguing. According to the study, it’s possible that yoga results in rapid gene expression alterations which may serve as the basis for their longer term cell biological and higher level health effects.

• The Effectiveness of Yoga for the Improvement of Well-being and Resilience to Stress in the Workplace: The purpose of this study was to test the effectiveness of yoga in promoting emotional well-being and resilience to stress among university employees. Findings include: the yoga group had significant improvements in measures of mood and well-being compared to the wait-list control group, reported greater improvements in feelings of clear-mindedness, composure, elation, energy, and confidence when compared to the wait-list control group at baseline and at the end of the program, and reported increased life purpose and satisfaction, and feelings of greater self-confidence during stressful situations.

Betsy’s Tips for Understanding and Evaluating Yoga Research

Become familiar with the types of studies and populations

• Case study: focuses on a particular person or group. This is the examination of an instance of phenomena. While it is difficult to generalize results from a case study to a larger population, this type of research can set the stage for more in-depth work to be done in that area. For more information, see case study.
• Meta-analysis: statistical technique for analyzing all data on a similar topic. This type of technique involves examining results from different studies of the same topic. A meta-analysis will provide effect sizes, which explain how much change occurred across studies. For more information, see meta-analysis or wiki.
• Clinical population: group of people affected with the particular phenomena being examined (i.e. anxiety disorder)
• Non-clinical population: group of people without a diagnosis of the phenomena being examined. For example, research can examine levels of depression in a group of people who have a diagnosis of depression (clinical) and also in people who do not (non-clinical).

Consider the study’s conclusion in light of its limitations (i.e small sample size, no control group)

• Sample size: indicates the number of participants in a research study. Small sample sizes are difficult to generalize from, while larger sample sizes usually provide more powerful results.
• Control group/comparison condition: group of participants who are not exposed to the treatment (i.e. yoga), or who are exposed to a treatment other than the target treatment (i.e. comparison: swimming, target treatment: yoga). For example, a study testing the effectiveness of a novel treatment strategy may use a control group exposed to a traditional intervention, no intervention, or even both. This would show how effective the novel intervention is compared to the traditional, and how the novel is compared to no intervention.
• Randomized Control Trials (RCTs): the gold standard for research methodology. RCTs simply mean that participants are assigned to either the expirmental or control/comparison group at random.
• Various yoga interventions: the current research on yoga includes many different types of yoga (anusara, ashtanga, bikram, etc.), so consider the type of yoga being studied when reading the conclusions and implications.
• Note: Because research is still untangling what the “active ingredients” of yoga are- what causes the effects- the best control group for use in yoga research is still unknown. A list of some comparison groups used in prior research include: exercise, relaxation, meditation, counseling, and education.