Yoga is a mind and body practice in complementary medicine with origins in ancient Indian philosophy. Part two of evidence based Yoga:
Carpal tunnel syndrome A randomized, single-blind controlled trial of 42 patients with carpal tunnel syndrome assigned subjects to either a yoga treatment group or a wrist splint group, each 8 weeks in duration. Twice a week, the yoga group practiced postures specifically designed to strengthen and stretch each joint in the upper body. Yoga participants showed improvement in grip strength, pain levels, and Phalen’s sign when compared to the wrist splint group. Nerve conduction studies were not performed.15 A Cochrane review of 21 trials that evaluated the clinical outcome of nonsurgical treatment of carpal tunnel syndrome reported that 8 weeks of yoga practice significantly reduced pain as compared to wrist splinting. The yoga was described as having a “significant short-term benefit,” though the duration of this benefit is unknown.16
Depression A 2004 review of five RCTs that evaluated yoga-based interventions for depression and depressive disorders showed some positive outcomes and no adverse effects on patients’ mild to severe depressive disorders. However, poor study design and incomplete methodologic reporting makes this interpretation preliminary.17 An RCT studying 7 weeks of yoga training in a group of breast cancer survivors showed positive changes in emotional function, depression, and mood disturbance.18 “Yoga and stress management” (in the online version of this article) provides more information on this study and others involving the effects of yoga on stress.
Irritable bowel syndrome In an RCT, treatment with loperamide (Imodium) was compared to treatment with a series of 12 yoga postures practiced twice a day for 2 months in a small sample of patients with clinically diagnosed irritable bowel syndrome. Patients underwent measurement of surface electrogastrography, and trait and state anxiety tests were administered before, during, and up to 2 months after treatment. Both intervention groups demonstrated a decrease in bowel symptoms and state anxiety.19
Menopausal symptoms In a recent pilot study, 14 postmenopausal women reported via interview and questionnaire a decrease in the severity and frequency of hot flushes after 8 weeks of 90-minute “restorative yoga” classes. Although this initial finding sounds encouraging, this trial had no control group or objective parameter measurements.20 An RCT studying postmenopausal sleep quality divided 164 women into groups who participated in either 4 months of low-intensity yoga, a moderate-intensity walking program, or a wait-list control group. This study reported no statistically significant interventional effects of any treatment on total sleep quality or on any individual sleep quality domain.21
Multiple sclerosis An RCT of 57 subjects with clinically defined multiple sclerosis were assigned to weekly Iyengar yoga class plus home practice, a cycling program, or a wait-list control group for 6 months. Results showed that both active interventions produced significant improvement in perceived levels of energy and reduced fatigue; however, the specific effects of the yoga practice were not isolated.22 Osteoarthritis In a pilot study, 11 deconditioned, yoga naive subjects with a clinical diagnosis of knee osteoarthritis showed improvements in pain and knee stiffness after 8 weeks of yoga training. The group performed modified Iyengar yoga sessions once a week.23
Seizure disorders In 2000, a systematic review of the published literature revealed that only one study was able to meet the selection criteria for reliable research design. The reviewers concluded that no available evidence pointed to yoga therapy as an efficacious treatment for epilepsy.24
Strength and flexibility In a recent study on the fitness related effects of hatha yoga, 10 yoga-naïve and previously untrained subjects aged 18 to 27 years participated in 85 minutes of pranayama and hatha yoga practice twice a week for 8 weeks. These subjects showed significant improvement in upper and lower body muscular strength, endurance, and flexibility. No statistically significant change in body composition or pulmonary function was observed.13
In a partial RCT with a longer time frame, 54 subjects aged 20 to 25 years participated in either 5 months of yoga instruction or no activity. After that time period, both groups practiced yoga for an additional 5 months. The group practicing 10 months of yoga showed significant improvements in shoulder, trunk, hip, and neck flexibility, as well as a reported improved performance during submaximal exercise testing.25
A well-executed study compared subjects who underwent 24 hours of hatha yoga classes over 8 weeks with a control group. The yoga training group showed a 13% to 35% improvement in flexibility, balance, and muscular endurance. The authors concluded that hatha yoga practice has significant effects on balance and flexibility.26
1. Tindle HA, Davis RB, Phillips RS, Eisenberg DM. Trends in use of complementary and alternative medicine by US adults: 1997-2002. Altern Ther Health Med. 2005;11(1):42-49.
2. Carrico M. Yoga Journal’s Yoga Basics: The Essential Beginner’s Guide to Yoga for a Lifetime of Health and Fitness. New York, NY: Henry Holt and Company; 1997.
3. Nayak NN, Shankar K. Yoga: a therapeutic approach. Phys Med Rehabil Clin N Am. 2004;15(4): 783-798, vi.
4. Innes KE, Bourguignon C, Taylor AG. Risk indices associated with the insulin resistance syndrome, cardiovascular disease, and possible protection with yoga: a systematic review. J Am Board Fam Pract. 2005;18(6):491-519.
5. Raub JA. Psychophysiologic effects of Hatha yoga on musculoskeletal and cardiopulmonary function: a literature review. J Altern Complement Med. 2002;8(6):797-812.
6. Luskin FM, Newell KA, Griffith M, et al. A review of mind-body therapies in the treatment of musculoskeletal disorders with implications for the elderly. Altern Ther Health Med. 2000;6(2): 46-56.
7. Jensen PS, Kenny DT. The effects of yoga on the attention and behavior of boys with attentiondeficit/ hyperactivity disorder (ADHD). J Atten Disord. 2004;7(4):205-216.
8. Kirkwood G, Rampes H, Tuffrey V, et al. Yoga for anxiety: a systematic review of the research evidence. Br J Sports Med. 2005;39(12):884-891.
9. Krisanaprakornkit T, Krisanaprakornkit W, Piyavhatkul N, Laopaiboon M. Meditation therapy for anxiety disorders. Cochrane Database Syst Rev. 2006;(1):CD004998.
10. Sabina AB, Williams AL, Wall HK, et al. Yoga intervention for adults with mild-to-moderate asthma: a pilot study. Ann Allergy Asthma Immunol. 2005;94(5):543-548.
11. Vendanthan PK, Kesavalu LN, Murthy KC, et al. Clinical study of yoga techniques in university students with asthma: a controlled study. Allergy Asthma Proc. 1998;19(1):3-9.
12. Sherman KJ, Cherkin DC, Erro J, et al. Comparing yoga, exercise, and a self-care book for chronic low back pain: a randomized, controlled trial. Ann Intern Med. 2005;143(12):849-856.
13. Tran MD, Holly RG, Lashbrook J, Amsterdam EA. Effects of Hatha yoga practice on the healthrelated aspects of physical fitness. Prev Cardiol. 2001;4(4):165-170.
14. Clay CC, Lloyd LK, Walker JL, et al. The metabolic cost of Hatha yoga. J Strength Cond Res. 2005;19(3):604-610.
15. Garfinkel MS, Singhal A, Katz WA, et al. Yoga-based intervention for carpal tunnel syndrome: a randomized trial. JAMA. 1998;280(18):1601-1603.
16. O’Connor D, Marshall S, Massy-Westropp N. Nonsurgical treatment (other than steroid injection) for carpal tunnel syndrome. Cochrane Database Syst Rev. 2003(1):CD003219.
17. Pilkington K, Kirkwood G, Rampes H, Richardson J. Yoga for depression: the research evidence. J Affect Disord. 2005;89(1-3):13-24.
18. Culos-Reed SN, Carlson LE, Daroux LM, Hately-Aldous S. A pilot study of yoga for breast cancer survivors: physical and psychological benefits. Psycho Oncol. 2006;15(10):891-897.
19. Taneja I, Deepak KK, Poojary G, et al. Yogic versus conventional treatment in diarrheapredominant irritable bowel syndrome: a randomized control study. Appl Psychophysiol Biofeedback. 2004;29(1):19-33.
20. Cohen BE, Kanaya AM, Macer JL, et al. Feasibility and acceptability of restorative yoga for treatment of hot flushes: a pilot trial. Maturitas. 2007;56(2):198-204.
21. Elavsky S, McAuley E. Lack of perceived sleep improvement after 4-month structured exercise programs. Menopause. 2007;14(3, pt 1):535-540.
22. Oken BS, Kishiyama S, Zajdel D, et al. Randomized controlled trial of yoga and exercise in multiple sclerosis. Neurology. 2004;62(11):2058-2064.
23. Kolasinski SL, Garfinkel M, Tsai AG, et al. Iyengar yoga for treating symptoms of osteoarthritis of the knees: a pilot study. J Altern Complement Med. 2005;11(4):689-693.
24. Ramaratnam S, Sridharan K. Yoga for epilepsy. Cochrane Database Syst Rev. 2000(3):CD001524.
25. Ray US, Mukhopadhyaya S, Purkayastha SS, et al. Effect of yogic exercises on physical and mental health of young fellowship course trainees. Indian J Physiol Pharmacol. 2001;45(1):37-53.
26. Boehde D, Porcari JP, Greany J, et al. The physiological effects of 8 weeks of yoga training. J Cardiopulm Rehabil. 2005;25(5):290.