Yoga was first described in Vedic texts of India and has been practiced over the centuries. It is an integral part of Ayurveda, the traditional healing system that originated in India. The major components of yoga are regulated breathing, moving through various postures, and meditation, aimed at achieving physical and emotional health benefits, with self-realization being the ultimate goal. There are many styles of yoga that encompass some or all of these components. In the United States, most practices focus on postures, meditation, and breath control (1).
Yoga has been shown in preliminary studies to effectively reduce symptoms of carpal tunnel syndrome (2), irritable bowel syndrome (3), asthma (4), drug-resistant epilepsy (5), and for weight maintenance(6), diabetes (7) migraine (8), AIDS (9) and depression (10). Further well designed clinical trials are needed to confirm these effects. A systematic review did not find yoga an effective intervention for anxiety (11). However, preliminary findings from another study show that yoga may help relieve anxiety by increasing the levels of a neurotransmitter GABA (12).
Analysis of a systematic review indicates that yoga is helpful in alleviating low back pain (13). Yoga can improve symptoms and quality of life in patients with paroxysmal atrial fibrillation (33).
With the introduction of yoga in many cancer centers across the country, patients now practice yoga for relief of symptoms and preliminary data are encouraging (14) (15). Studies in breast cancer survivors indicate that yoga has physical and psychological benefits by improving social functioning (16), improving mood, and reducing stress levels (17); reduction in number of hot flashes, fatigue (18), joint pain was associated with a yoga program in early-stage breast cancer survivors and the benefits persisted at the 3-month follow-up (19). In another study, practice of Tibetan yoga, which incorporates controlled breathing, visualization, mindfulness techniques, and low-impact postures, improved sleep quality in patients with lymphoma (20). Yoga also reduced stress, increased a sense of well-being, and resulted in more restful sleep in both newly diagnosed cancer patients and survivors (21) (22) (23). An eight-week mindfulness-based stress reduction program involving relaxation, meditation, and gentle yoga was shown to significantly improve symptoms of stress and overall quality of life in breast and prostate cancer outpatients (24). A meta-analysis of nine studies of cancer patients concluded that yoga may be an effective intervention for improving quality of life of cancer patients (1).
Adverse effects associated with improper Yoga practice have been reported. These include hematoma (25) (10), nerve damages (26), aggravation of glaucoma (27) (28), embolism (29), ligament rupture (30), and spontaneous pneumothorax (31) (32). Cancer patients interested in beginning yoga should first consult their physicians. Because of limitations due to surgery, chemotherapy, and radiotherapy, it is advisable to learn the proper technique from certified instructors who have experience working with cancer patients.