At some point between the 1st and 5th century CE, the Hindu sage Patañjali began to codify
the ancient meditative traditions practiced throughout India. He recorded techniques nearly as old 
as Indian civilization itself in 196 manuals called the Yoga Sutras. These texts defined yoga as the ‘yoking’ 
or restraining of the mind from focusing on external objects in efforts to reach a state 
of pure consciousness. Over time, yoga came to incorporate
physical elements from gymnastics and wrestling. Today, there are a multitude of approaches
to modern yoga—though most still maintain the three core
elements of Patañjali’s practice: physical postures, breathing exercises, 
and spiritual contemplation. This blend of physical 
and mental exercise is widely believed to have a unique set 
of health advantages, such as improving strength
and flexibility, boosting heart and lung function, 
and enhancing psychological well-being. But what have contemporary studies shown
regarding the benefits

of this ancient tradition? Despite attempts by many researchers, it's tough to make specific claims 
about yoga's advantages. Its unique combination of activities 
makes it difficult to determine which component is producing 
a specific health benefit. Additionally, yoga studies are often 
made up of small sample sizes that lack diversity, and the heavy reliance on self-reporting
makes results subjective. However, there are some health benefits that have more robust scientific 
support than others. Let’s start with flexibility and strength. Twisting your body 
into yoga’s physical postures stretches multiple muscle groups. In the short term, stretching can change
the water content of these muscles, ligaments, and tendons 
to make them more elastic. Over time, regular stretching 
stimulates stem cells, which then differentiate 
into new muscle tissue and other cells that generate 
elastic collagen. Frequent stretching also reduces 
the body’s natural reflex to constrict muscles, improving your pain tolerance 
for feats of flexibility.

Researchers haven’t found that any one form of yoga improves flexibility more than another, so the impact of specific postures is unclear. But like other low-impact exercises, yoga reliably improves fitness and flexibility in healthy populations. The practice has also been shown to be a potentially powerful therapeutic tool. In studies involving patients with a variety of musculo-skeletal disorders, yoga was more helpful at reducing pain and improving mobility than other forms of low-impact exercise. Adding yoga to an existing exercise routine can improve strength and flexibility for hard-to-treat conditions like chronic lower back pain, rheumatoid arthritis, and osteoporosis. Yoga’s mix of physical exercise and regimented breathing has proven similarly therapeutic for lung health. Lung diseases like chronic bronchitis, emphysema, and asthma shrink the passageways that carry oxygen, while weakening the membrane that brings oxygen into the blood. But breathing exercises like those found in yoga

relax the muscles constricting 
those passageways and improve oxygen diffusion. Increasing the blood’s oxygen content,
is especially helpful for those with weak heart muscles who have difficulty pumping
enough oxygen throughout the body. And for those with healthy hearts, this practice can lower blood pressure,
and reduce risk factors for cardiovascular disease. Yoga’s most widely celebrated benefit,
may be the most difficult to prove: its psychological effects. Despite the longstanding association 
between yoga and psychological wellbeing, there’s little conclusive evidence 
on how the practice affects mental health. One of the biggest claims is that yoga improves symptoms 
of depression and anxiety disorders. Since diagnosis of these conditions,
varies widely as do their origin and severity,
it’s difficult to quantify yoga’s impact. However, there is evidence to suggest that yoga can help reduce 
the symptoms of stress, as well as meditation or relaxation. Research on the effects 
of yoga is still evolving. In the future, we’ll need larger studies, 
incorporating diverse participants.

which can measure yoga’s impact
on heart attacks, cancer rates, cognitive function, and more. But for now, yoga can continue 
its ancient tradition as a way to exercise, reflect, and relax.

What yoga does to your body and brain - Krishna Sudhir

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