The Science of Yoga: The Risks and the Rewards

by William J Broad

  58 spreading slowly through India: For a case study of its adoption by the Raja of Aundh, the ruler of a diminutive state north of Mysore, see Katherine H. Diver, Royal India: A Descriptive and Historical Study of India’s Fifteen Principal States and Their Rulers (London: Hodder & Stoughton, 1942), pp. 148–50.

  58 learned about the pose: In 1959, a popular book by Swami Vishnudevananda, a young disciple of Swami Sivananda’s, gained wide notice. It was filled with dozens of photographs of the young swami and clear, how-to directions, including eleven pages devoted to the Sun Salutation. See Swami Vishnudevananda, The Complete Illustrated Book of Yoga (New York: Bell Publishing, 1960).

  59 examined sixteen volunteers: Virginia S. Cowen and Troy B. Adams, “Heart Rate in Yoga Asana Practice: A Comparison of Styles,” Journal of Bodywork and Movement Therapies, vol. 11, no. 1 (January 2007), pp. 91–95.

  59 “the lack of objective study”: Email to author, Ezra A. Amsterdam, October 22, 2011.

  60 “many lively discussions”: Email to author, Dina Amsterdam, October 26, 2011. For background on Amsterdam’s yoga study and Dina’s role, see Alisa Bauman, “Is Yoga Enough to Keep You Fit?” Yoga Journal, September–October 2002, p. 84.

  60 just ten volunteers: Mark D. Tran, Robert G. Holly, Jake Lashbrook, and Ezra A. Amsterdam, “Effects of Hatha Yoga Practice on the Health-Related Aspects of Physical Fitness,” Preventive Cardiology, vol. 4, no. 4, (Fall 2001), pp. 165–70.

  61 Different schools of yoga: The Iyengar Frog is a static posture. See Iyengar, Light on Yoga, pp. 126–28. The energetic Frog of the Davis study is taught by the Kundalini school. See Shakta Kaur Khalsa, Kundalini Yoga: Unlock Your Inner Potential Through Life-Changing Exercise (New York: Dorling Kindersley, 2001), pp. 55, 72, 100, 129.

  62 making their evaluation “blind”: Emails to author, Ezra A. Amsterdam, October 22 and 23, 2011. Amsterdam said reviewers for the journal once rejected a paper on which he was listed as a coauthor, showing how the process was unbiased.

  64 “the most current scientific information”: Anonymous, “The Yoga Journal Story,” www.yogajournal.com/global/

  64 “Yoga is all you need”: Bauman, “Is Yoga Enough to Keep You Fit?”

  64 a commercial style: Beth Shaw, Beth Shaw’s YogaFit (Champaign, IL: Human Kinetics, 2000), pp. ix–xvi; Beth Greenfield, “Strike a Pose,” Out, February 2004, p. 78.

  65 developed a course of training: Kolata, Ultimate Fitness, p. 247.

  65 “a tough cardiovascular workout”: Shaw, Beth Shaw’s, p. ix.

  65 Her promotional literature: Anonymous, “Host a Yoga Instructor Training,” www.yogafit.com/host-a-training.shtml.

  65 The sixteen-page paper: Chrys Kub, “Health Benefits of Hatha Yoga,” www.yogafit.com/research/healthbenefits.doc.

  65 “You don’t need”: Alexa Joy Sherman, “Total Body Power Yoga,” Shape, vol. 24, no. 3 (November 2004), pp. 186–91.

  66 a young scientist who practiced yoga: Emails to author, Carolyn C. Clay, Texas State University, June 9 and 15, 2011.

  66 Their study appeared: Carolyn C. Clay, Lisa K. Lloyd, John L. Walker, et al., “The Metabolic Cost of Hatha Yoga,” The Journal of Strength and Conditioning Research, vol. 19, no. 3 (August 2005), pp. 604–10.

  68 more emphasis on the vigorous pose: For a scientific evaluation of the Sun Salutation as an exclusive path to cardiovascular fitness, see Bhavesh Surendra Mody, “Acute effects of Surya Namaskar on the cardiovascular & metabolic system,” Journal of Bodywork and Movement Therapies, vol. 15, no. 3 (July 2011), pp. 343–47.

  68 done at the University of Wisconsin: Dawn D. Boehde, John P. Porcari, John Greany, et al., “The Physiological Effects of 8 Weeks of Yoga Training,” Journal of Cardiopulmonary Rehabilitation, vol. 25 (2005), p. 290.

  68 “The intensity just wasn’t there”: Quoted in Mark Anders, “Does Yoga Really Do the Body Good?” American Council on Exercise, ACE Fitness Matters, September–October 2005, pp. 7–9.

  68 sent out a press release: Anonymous, “ACE First to Evaluate Benefits of Yoga,” the American Council on Exercise, September 28, 2005, www.acefit ness.org/pressroom/419/ace-first-to-evaluate-benefits-of-yoga-br-i.

  69 “Aerobics?”: John Briley, “Aerobics? Not Among Yoga’s Strengths,” Washington Post, October 11, 2005, p. F3.

  69 Yoga Journal took notice: Sierra Senyak, “Flexible and Fit,” Yoga Journal, June 2006, p. 22.

  69 “I think you just proved”: Mia, reader comment on “Flexible and Fit,” www.yogajournal.com/lifestyle/2275.

  69 A final study: Marshall Hagins, Wendy Moore, and Andrew Rundle, “Does Practicing Hatha Yoga Satisfy Recommendations for Intensity of Physical Activity Which Improves and Maintains Health and Cardiovascular Fitness?” BMC Complementary and Alternative Medicine, vol. 7, no. 40 (November 30, 2007), www.biomedcentral.com/1472-6882/7/40.

  70 The lead scientist: Anonymous, “Despite Other Health Benefits, Yoga May Not Lead to Cardio Fitness Says Researcher at Long Island University’s Brooklyn Campus in New Study,” news release, Brooklyn campus of Long Island University, January 8, 2008, www.brooklyn.liu.edu/wn/2008/004.html.

  70 Known as a metabolic chamber: Interview, Marshall Hagins, Long Island University, July 21, 2010.

  73 examined more than eighty studies: Alyson Ross and Sue Thomas, “The Health Benefits of Yoga and Exercise: A Review of Comparison Studies,” Journal of Alternative and Complementary Medicine, vol. 16, no. 1 (January 2010), pp. 3–12.

  74 “a good cardio workout”: Anonymous, “What’s Your Style, Baby?” Yoga Journal, February 2008, p. A7.

  74 “aerobic benefits”: Georg Feuerstein and Larry Payne, Yoga for Dummies, 2nd ed. (Indianapolis: Wiley, 2010), p. 172.

  74 a frequent question of readers: Ann Pizer, “Does Yoga Keep You Fit?” About.com, December 11, 2008, http://yoga.about.com/b/2008/12/11/does-yoga-keep-you-fit.htm.

  74 advised readers that vigorous styles: Michael J. O’Fallon and Denney G. Rutherford, Hotel Management and Operations, 5th ed. (Hoboken, NJ: Wiley, 2010), p. 41.

  74 Huffington Post ran a link: Verena von Pfetten, “Is Yoga Really Enough To Keep You Fit?,” Huffington Post, July 31, 2008, www.huffingtonpost.com/2008/07/31/is-yoga-really-enough-to_n_116158.html.

  75 asked its readers in 2010: Ivy Markaity, “Does Yoga Provide Enough of a Cardio Workout?” HealthCentral.com, August 27, 2010, www.healthcentral.com/diet-exercise/c/223360/118686/workout.

  75 runs a school in Los Angeles: Lee Jenkins, “Deep Breath as Pitchers Rethink Routines,” New York Times, February 12, 2007, Section D, p. 1.

  III: Moods

  78 “What ever happened”: Interview, Sat Bir Khalsa, Harvard Medical School, May 15, 2007.

  79 more important than money: Robert E. Thayer, The Origin of Everyday Moods (New York: Oxford University Press, 1996), pp. 3–42.

  79 first definitions: The Compact Edition of The Oxford English Dictionary (Oxford: Oxford University Press, 1971), vol. 1, p. 1844; Albert C. Baugh and Thomas Cable, A History of the English Language (London: Routledge, 1993), p. 63.

  79 The conventional wisdom: American Psychiatric Association, the Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (Washington: American Psychiatric Association, 1994), p. 341.

  79 A survey found: Laura A. Pratt, Debra J. Brody, and Qiuping Gu, “Antidepressant Use in Persons Aged 12 and Over: United States, 2005–2008,” U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Health and Nutrition Examination Surveys, Data Brief No. 76, October 2011.

  79 “It really saved”: Yoga class with Amy Weintraub, Kripalu Yoga Center, Stockbridge, Massachusetts, November 12, 2010.

  80 “as through a fog”: Amy Weintraub, Yoga for Depression: A Compassionate Guide to Relieve Suffering Through Yoga (New York: Broadway Books, 2004), p. 2.

  80 a book in the works: Amy Weintraub, Yoga Skills for Therapists: Mood-Management Techniques to Teach & Practice (New York: Norton, 2012).

  80 core attracti
on of Kripalu: For an overview of the center, see Andy Newman, “It’s Not Easy Picking a Path to Enlightenment,” New York Times, July 3, 2008, Section G, p. 1.

  80 “Free in this world”: Quoted in David H. Albert, “Thoreau’s India: The Impact of Reading in a Crisis,” Proceedings of the American Philosophical Society, vol. 125, no. 2 (April 30, 1981), p. 107.

  80 the first known instance: De Michelis, A History, pp. 2–3.

  81 looked favorably on yoga: William James, On Vital Reserves: The Energies of Men, The Gospel of Relaxation (New York: Henry Holt, 1922), pp. 26–29.

  81 simple but systematic relaxation: William James, The Varieties of Religious Experience (New York: Longmans, Green, 1902), pp. 110–15.

  81 following the lead of James: F. J. McGuigan and Paul M. Lehrer, “Progressive Relaxation: Origins, Principles, and Clinical Application,” in Paul M. Lehrer, Robert L. Woolfolk, Wesley E. Sime, et al., eds., Principles and Practice of Stress Management, 3rd ed. (New York: Guilford Press, 2007), pp. 57–87.

  81 subjects had no obvious reaction: Edmund Jacobson, Progressive Relaxation: A Physiological and Clinical Investigation of Muscular States and Their Significance in Psychology and Medical Practice (Chicago: University of Chicago Press, 1931), pp. 101–11.

  82 taught himself how to relax: Ibid., p. 111.

  82 produced remarkable cures: Ibid., pp. 309–79.

  82 suffered a skull fracture: Edmund Jacobson, “The Neurovoltmeter,” American Journal of Psychology, vol. 52, no. 4 (October 1939), pp. 620–24.

  83 graduated from the University: Kovoor T. Behanan, Yoga: A Scientific Evaluation (New York: Macmillan, 1937), pp. xii–xiii.

  83 journeyed to the world capital: The arrangement carried a risk of conflict, given that Gune was a true believer and Behanan an outsider committed, in theory, to scientific doubt. But Gune was gracious, and Yale politic. Behanan’s advisor, Walter R. Miles, a professor at Yale’s Institute of Human Relations, said Gune saw his new student as having a “sympathetic and genuine desire to study the system of Yoga objectively and critically.” See ibid, p. xiv.

  83 practiced every day: Ibid., p. 229.

  83 did the exercise at a rate: Ibid., p. 237.

  83 psychological testing: Ibid., pp. 228–32.

  84 Life ran a formal portrait: Anonymous, “Speaking of Pictures . . . These are the Exercises of Yoga,” Life, April 19, 1937, pp. 8–9.

  84 a glowing review: Anonymous, “Yale’s Yogin,” Time, April 26, 1937, p. 24

  84 “a retardation of mental functions”: Behanan, Yoga, p. 232.

  84 “an extremely pleasant feeling”: Ibid., p. 243.

  84 “emotional stability”: Ibid., p. 245.

  84 a spike in oxygen consumption: Ibid., p. 237.

  85 exploits this ocean: McArdle et al., Exercise Physiology, pp. 282–85.

  85 nearly saturated with oxygen: Richard M. Schwartzstein and Michael J. Parker, Respiratory Physiology: A Clinical Approach (Philadelphia: Lippincott Williams & Wilkins, 2006), p. 109.

  85 large quantities no matter what: An exception arises when the lungs are diseased or impaired, at which point slow breathing may aid oxygenation. See Luciano Bernardi, Giammario Spadacini, Jerzy Bellwon. et al., “Effect of Breathing Rate on Oxygen Saturation and Exercise Performance in Chronic Heart Failure,” Lancet, vol. 351 (May 2, 1998), pp. 1308–11.

  85 creating an inner environment: McArdle et al., Exercise Physiology, pp. 280–81.

  86 “lowers body stores”: U.S. Navy, U.S. Navy Diving Manual, Revision Five, vol. 1, (Washington, DC: Naval Sea Systems Command, 2005), p. 3–19.

  86 respiratory alkalosis: Schwartzstein and Parker, Respiratory Physiology, pp. 155–56; Carol Mattson Porth, Essentials of Pathophysiology (Philadelphia: Lippincott Williams & Wilkins, 2007), p. 147; Burton David Rose and Theodore W. Post, Clinical Physiology of Acid-Base and Electrolyte Disorders (New York: McGraw-Hill, 2001), pp. 673–81.

  86 “a feeling of exhilaration”: Iyengar, Light on Pranayama, p. 179.

  86 vessels in the brain to contract: Ronald Ley, “Breathing and the Psychology of Emotion, Cognition, and Behavior,” in Beverly H. Timmons and Ronald Ley, eds., Behavioral and Psychological Approaches to Breathing Disorders (New York: Kluwer, 1994), pp. 86–88; L. C. Lum, “Hyperventilation Syndromes,” in Timmons and Ley, Behavioral, pp. 119–20.

  86 cuts levels roughly in half: Ibid., p. 119; for an early study, see Seymour S. Kety and Carl F. Schmidt, “The Effects of Active and Passive Hyperventilation on Cerebral Blood Flow, Cerebral Oxygen Consumption, Cardiac Output, and Blood Pressure of Normal Young Men,” Journal of Clinical Investigation, vol. 25 (1946), pp. 107–19.

  87 three scientists in Sweden: C. Frostell, J. N. Pande, and G. Hedenstierna, “Effects of high-frequency breathing on pulmonary ventilation and gas exchange,” Journal of Applied Physiology, vol. 55, no. 6 (1983), pp. 1854–61.

  88 a standard figure: Porth, Essentials, p. 515.

  88 brain now gets more oxygen: Ibid., p. 147.

  88 increases in calm alertness: Richard P. Brown and Patricia L. Gerbarg, “Sudarshan Kriya Yogic Breathing in the Treatment of Stress, Anxiety, and Depression: Part I—Neurophysiologic Model,” Journal of Alternative and Complementary Medicine, vol. 11, no. 1 (2005), pp. 189–201.

  88 linked slow breathing to heightened vigilance: Dirk S. Fokkema, “The Psychobiology of Strained Breathing and Its Cardiovascular Implications: A Functional System Review,” Psychophysiology, vol. 36, no. 2 (March 1999), pp. 164–75.

  88 a study of nearly two dozen adults: Luciano Bernardi, Peter Sleight, Gabriele Bandinelli, et al., “Effect of Rosary Prayer and Yoga Mantras on Autonomic Cardiovascular Rhythms: A Comparative Study,” British Medical Journal, vol. 323 (2001), pp. 1446–49.

  88 “You’re not used”: Choudhury, Bikram Yoga, p. 101.

  88 Kundalini Yoga: Khalsa, Kundalini Yoga, p. 25.

  88 “one of the best things”: Budilovsky and Adamson, The Complete Idiot’s Guide, p. 302.

  89 “for anyone in need”: Anonymous, “Yoga Instructional Book ‘Oxygen Yoga: A Spa Universe’ Now Available,” WiredPRNews.com, August 15, 2011.

  89 wrote extensively: Her writings were often in French. For an English work, see Thérèse Brosse, “A Psycho-physiological Study,” Main Currents in Modern Thought, no. 4 (July 1946), pp. 77–84.

  89 “an extreme slowing”: B. K. Bagchi and M. A. Wenger, “Electro-physiological Correlates of Some Yogi Exercises,” EEG and Clinical Neurophysiology, 1957, supplement 7, p. 146.

  90 a gap of up to eleven degrees: Elmer and Alyce Green, Beyond Biofeedback (New York: Delacorte Press, 1977), pp. 197–205.

  90 biologists called it “sympathetic”: Stanley Finger, Origins of Neuroscience: A History of Explorations into Brain Function (New York: Oxford University Press, 2001), pp. 280–84.

  91 “My name is Mel”: Yoga class with Mel Robin, Yoga Loft, Bethlehem, Pennsylvania, April 14, 2007.

  93 cast the topic: Yoga class with Mel Robin, Yoga Loft, Bethlehem, Pennsylvania, July 24, 2007.

  94 a place in his book: Robin, A Physiological Handbook, pp. 137–40.

  94 had us turn to another page: Ibid., p. 147.

  95 The Relaxation Response: Herbert Benson and Miriam Z. Klipper, The Relaxation Response (New York: HarperCollins, 2000).

  96 average of 13 percent: Chaya et al., “The Effect of Long Term Combined Yoga Practice.” See also M. S. Chaya and H. R. Nagendra, “Long-term effect of yogic practices on diurnal metabolic rates of healthy subjects,” International Journal of Yoga, vol. 1, no. 1 (January–June 2008), pp. 27–32.

  97 New York Times profiled: Lizette Alvarez, “Rebel Yoga,” New York Times, January 23, 2011, Section WE, p. 1.

  97 “rev up your metabolism”: Tara Stiles, Slim Calm Sexy Yoga (New York: Rodale, 2010), p. 150.

  98 “Yoga affects the mind”: Interview, Mayasandra S. Chaya, Swami Vivekananda Yoga Research Foundation, Bangalore, India, June 13, 2011.

  98 nearly one million de
spairing people: Anonymous, “Depression,” World Health Organization.

  99 known about GABA since the 1950s: Max R. Bennett, History of the Synapse (Amsterdam: Harwood Academic Publishers, 2001), pp. 83–85.

  100 published in 2007: Chris C. Streeter, J. Eric Jensen, Ruth M. Perlmutter, et al., “Yoga Asana Sessions Increase Brain GABA Levels: A Pilot Study,” Journal of Alternative and Complementary Medicine, vol. 13, no. 4 (2007), pp. 419–26.

  100 “clear public health advantages”: Quoted in Gina M. Digravio, “Study Finds Yoga Associated with Elevated Brain GABA Levels,” Boston University news release, May 22, 2007.