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At some point between 
the 1st and 5th century CE,

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the Hindu sage Patañjali began to codify
the ancient, meditative traditions

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practiced throughout India.

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He recorded techniques nearly as old 
as Indian civilization itself

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in 196 manuals called the Yoga Sutras.

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These texts defined yoga as the ‘yoking’ 
or restraining of the mind

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from focusing on external objects

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in efforts to reach a state 
of pure consciousness.

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Over time, yoga came to incorporate
physical elements

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from gymnastics and wrestling.

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Today, there are a multitude of approaches
to modern yoga—

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though most still maintain the three core
elements of Patañjali’s practice:

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physical postures, breathing exercises, 
and spiritual contemplation.

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This blend of physical 
and mental exercise

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is widely believed to have a unique set 
of health advantages.

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Such as improving strength
and flexibility,

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boosting heart and lung function, 
and enhancing psychological well-being.

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But what have contemporary studies shown
regarding the benefits

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of this ancient tradition?

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Despite attempts by many researchers,

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it's tough to make specific claims 
about yoga's advantages.

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Its unique combination of activities 
makes it difficult to determine

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which component is producing 
a specific health benefit.

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Additionally, yoga studies are often 
made up of small sample sizes

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that lack diversity,

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and the heavy reliance on self-reporting
makes results subjective.

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However, there are some health benefits

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that have more robust scientific 
support than others.

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Let’s start with flexibility and strength.

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Twisting your body 
into yoga’s physical postures

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stretches multiple muscle groups.

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In the short term, stretching can change
the water content of these muscles,

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ligaments, and tendons 
to make them more elastic.

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Over time, regular stretching 
stimulates stem cells

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which then differentiate 
into new muscle tissue

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and other cells that generate 
elastic collagen.

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Frequent stretching also reduces 
the body’s natural reflex

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to constrict muscles,

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improving your pain tolerance 
for feats of flexibility.

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Researchers haven’t found 
that any one form of yoga

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improves flexibility more than another,

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so the impact of specific 
postures is unclear.

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But like other low-impact exercises,

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yoga reliably improves fitness 
and flexibility in healthy populations.

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The practice has also been shown to be
a potentially powerful therapeutic tool.

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In studies involving patients with 
a variety of musculo-skeletal disorders,

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yoga was more helpful at reducing pain 
and improving mobility

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than other forms of low-impact exercise.

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Adding yoga to an existing 
exercise routine can improve strength

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and flexibility for hard to treat 
conditions like chronic lower back pain,

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rheumatoid arthritis, and osteoporosis.

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Yoga’s mix of physical exercise 
and regimented breathing

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has proven similarly therapeutic 
for lung health.

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Lung diseases like chronic bronchitis, 
emphysema, and asthma

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shrink the passageways that carry oxygen,

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while weakening the membrane 
that brings oxygen into the blood.

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But breathing exercises 
like those found in yoga

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relax the muscles constricting 
those passageways

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and improve oxygen diffusion.

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Increasing the blood’s oxygen content
is especially helpful

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for those with weak heart muscles

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who have difficulty pumping
enough oxygen throughout the body.

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And for those with healthy hearts,

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this practice can lower blood pressure
and reduce risk factors

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for cardiovascular disease.

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Yoga’s most widely celebrated benefit
may be the most difficult to prove:

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its psychological effects.

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Despite the longstanding association 
between yoga and psychological wellbeing,

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there’s little conclusive evidence 
on how the practice affects mental health.

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One of the biggest claims

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is that yoga improves symptoms 
of depression and anxiety disorders.

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Since diagnosis of these conditions
varies widely

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as do their origin and severity,
it’s difficult to quantify yoga’s impact.

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However, there is evidence to suggest

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that yoga can help reduce 
the symptoms of stress,

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as well as meditation or relaxation.

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Research on the effects 
of yoga is still evolving.

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In the future, we’ll need larger studies, 
incorporating diverse participants,

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which can measure yoga’s impact
on heart attacks, cancer rates,

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cognitive function and more.

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But for now, yoga can continue 
its ancient tradition

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as a way to exercise, reflect, and relax.