A Hindu spiritual and ascetic discipline, a part of which, including breath control, simple meditation, and the adoption of specific bodily postures, is widely practised for health and relaxation .
Yoga originated thousands of years ago in India as an integrated physical, mental, and spiritual practice based on ancient Vedic philosophy, and is connected to Ayurveda, the system of traditional Indian medicine. During the 20th century, yoga became increasingly recognised outside India, and over the past decades it has continued to grow in popularity worldwide as system for promoting health and well-being. While modern yoga often focuses on physical poses and is sometimes thought of as a type of exercise, the practice usually incorporates one or more of the mental or spiritual elements that are traditionally part of yoga, such as relaxation, concentration, or meditation. For this reason, yoga is considered a mind-body exercise.
Yoga and chronic nonspecific low back pain
Chang et al in their conducted systematic review revealed that yoga can reduce pain and disability, can be practiced safely, and is well received by participants. Some of randomized control trial (RCT) studies   in their review indicate that yoga may improve psychological symptoms, but these effects are currently not as well established . Accordind to Beggs et al the strongest and most consistent evidence in their meta- analysis study emerged for the short-term benefits of yoga on functional disability. However, before any definitive conclusions can be drawn, there are a number of methodological concerns that need to be addressed. In particular, it is recommended that future RCTs include an active control group to determine whether yoga has specific treatment effects and whether yoga offers any advantages over traditional exercise programs and other alternative therapies for chronic low back pain .
Yoga and cardiovascular diseases
Krishna et al in their RCT study has found that yoga therapy in addition to standard medical therapy reduces blood pressure, load on heart and improves parasympathetic activity and decreased the sympatic activity in heart failure patients .Wolf et al in a controlled study has found that a short yoga program for the patients diagnosed with hypertension to practice at home seems to have an antihypertensive effect, as well as a positive effect on self-rated quality of life compared to controls. This implies that simple yoga exercises may be useful as a supplementary blood pressure therapy in addition to medical treatment when prescribed by primary care physicians.
Yoga and cancer patients
Results from a systematic review conducted by Sadja and Mills revealed that yoga interventions may be beneficial for reducing cancer-related fatigue in women with breast cancer .Sharma et al in their systematic review has also found positive evidence of yoga as an altenative and complementary treatment. Though there has been liminations in the reviewed studies . In a recently published systematic review by Agarwal and Adi Maroko-Afek has been found that yoga improved the physical and psychological symptoms, quality of life, and markers of immunity of the patients, providing a strong support for yoga's integration into conventional cancer care .
- Oxford dictionaries. https://en.oxforddictionaries.com/definition/yoga(Accessed 10 marts 2018).
- Cochrane Library. http://www.cochranelibrary.com/app/content/special-collections/article/?doi=10.1002/14651858.YFIHWB (Accessed 10 marts 2018).
- Williams KA, Petronis J, Smith D, Goodrich D, Wu J, Ravi N et al. Effect of Iyengar yoga therapy for chronic low back pain.Pain. 2005 May;115(1-2):107-17.
- Tilbrook HE, Cox H, Hewitt CE, Kang'ombe AR, Chuang LH, Jayakody S et al. Yoga for chronic low back pain: a randomized trial. Ann Intern Med. 2011 Nov 1;155(9):569-78.
- Douglas G Chang, Jacquelyn A Holt, Marisa Sklar, Erik J Groessl.Yoga as a treatment for chronic low back pain: A systematic review of the literature. J Orthop Rheumatol. 2016; January 1; 3(1): 1–8.
- Beggs T,Holtzman S. Yoga for chronic low back pain: a meta-analysis of randomized controlled trials. Pain Research and Management.2013 Sep-Oct;18(5):267-72.
- Krishna B, Pal P,Gaur GS, et al. Effect of Yoga Therapy on Heart Rate, Blood Pressure and Cardiac Autonomic Function in Heart Failure. JCDR 2014;Jan;8(1):14-6.
- Wolff M, Sundquist S et al. Impact of yoga on blood pressure and quality of life in patients with hypertension - a controlled trial in primary care, matched for systolic blood pressure. BMC Cardiovasc Disord, 2013 Dec 7;13:111.
- Sadja J, Mills P. Effects of yoga interventions on fatigue in cancer patients and survivors: a systematic review of randomized controlled trials. Explore (NY). 2013 Jul-Aug;9(4):232-43.
- Sharma M, Haider T, Knowlde A.Yoga as an alternative and complementary treatment for cancer: a systematic review. J Altern Complement Med. 2013 Nov;19(11):870-5.
- Agarwal RP, Maroko A.Yoga into Cancer Care: A Review of the Evidence-based Research.Int J Yoga. 2018 Jan-Apr;11(1):3-29.