Iyengar Yoga, created by B. K. S. Iyengar, is a form of yoga known for its use of props, such as belts and blocks, as aids in performing asanas (postures). It is firmly based on the traditional eight limbs of yoga as expounded by Patanjali in his Yoga Sutras, emphasizing the development of strength, stamina, flexibility and balance, as well as concentration (Dharana) and meditation (Dhyana).
A form of Hatha Yoga, it focuses on the structural alignment of the physical body through the development of asanas. Through the practice of a system of asanas, it aims to unite the body, mind and spirit for health and well-being. This discipline is considered a powerful tool to relieve the stresses of modern-day life which in turn can help promote total physical and spiritual well-being.
Iyengar Yoga is characterized by great attention to detail and precise focus on body alignment. Iyengar pioneered the use of "props" such as cushions, benches, blocks, straps, and even sand bags, which function as aids allowing beginners to experience asanas more easily and fully than might otherwise be possible without several years of practice. Props also allow tired or ill students to enjoy the benefits of many asanas via fully "supported" methods requiring less muscular effort.
Standing poses are emphasized in Iyengar Yoga. They are said to build strong legs, increase general vitality, and improve circulation, coordination and balance, ensuring a strong foundation for study of more advanced poses.
Unlike more experiential approaches where students are encouraged to independently "find their way" to the asanas by imitating the teacher, an Iyengar Yoga class is highly verbal and precise, with misalignments and errors actively corrected. Iyengar teachers complete at least two years of rigorous training for the introductory certificate. They may complete subsequent intermediate levels and senior levels of certification, potentially entailing a decade or more of training.
Iyengar also developed extensively ways of applying his practice to various ailments, diseases, and disorders. Many of these sources of suffering, such as chronic backache, immunodeficiency, high blood pressure, insomnia, depression and menopause, have specific programs of Iyengar yoga associated with them. Iyengar himself worked with patients after patients had myocardial infarctions. The asanas can be adjusted based on the patient's stage of recovery. These programs are formulated in their most advanced form at the centre of Iyengar Yoga: the Ramamani Iyengar Memorial Yoga Institute located in Pune, India.
There have been many studies performed on the effects of Iyengar yoga on patients with physical problems. In general, Iyengar yoga is useful in physical therapy because it assists in the manipulation of inflexible or injured areas. One study by Dr. Sharon Kolasinski et al. studied the effects of Iyengar yoga on symptoms of osteoarthritis of the knees. The 11 participants attended a weekly 90-minute session for eight weeks in which they practiced Iyengar yoga. After the program, they had reduced pain and disability. This study had some limitations in that only 11 patients were involved and there was no control group.
In another study of Iyengar yoga, it was shown to be promising as a complementary treatment for depression. Shapiro et al. performed this study in which 17 participants that suffered from major unipolar depression attended at least six sessions of Iyengar yoga. At the end, they reported a reduction in depression, anxiety, and anger. This was a pilot study with a single-group outcome design and no placebo or other control group. The study concluded that yoga is cost-effective and easy to implement and that it produces many beneficial emotional, psychological, behavioral, and biological effects.