The origins of yoga are not very clear, although many in India believe that the practice began during ancient times under the tutelage of the learned sage, Patanjali.

One of India's most popular yoga teachers, B.K.S. Iyengar, says in his book Light on Life: "Patanjali...is considered the father of yoga. In reality, as far as we know, he was a yogi and a polymath living around fifth century B.C India, who collated and elaborated existing knowledge of the yogis' life and practices. He wrote the Yoga Sutras, literally, a thread of aphorisms about yoga, consciousness and the human condition."

"Yoga is as old as the universe itself," said Sanjay Singh, a professor at the University of Patanjali in Haridwar, India. "Yoga is a practice taught by god himself. It was not created by human beings and the purpose of yoga is to know the reality of life, to free the self from the cycle of life and death." 

The word "yoga" means "to be united, to be one with god and to be one with your real self, to know who you are, the purpose of your life and the best way to live your life," Singh added.

What it is today

Today, yoga is not just restricted to India, but has become globally popular as a means to achieve physical fitness and peace of mind. Yoga schools, in India and the West, teach many forms of the practice, including Hatha Yoga, Iyengar Yoga, Ashtanga Yoga, Vinyasa Yoga, Bikram Yoga and Hot Yoga, all of which offer different ways of achieving the goal of physical fitness and relaxation.

The increasing demand for yoga among different groups of people has resulted in more innovation as far as the practice is concerned. Thus dog owners, for instance, can take their pets to their practice and do what is called Dog Yoga. Naked yoga involves doing asanas in the nude, reducing self-consciousness and accepting imperfections in the body. Beer yoga, a trend that emerged in Berlin, targets beer drinkers, who want to get some exercise while sipping their favorite beverage.

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Although these modifications have helped increase the popularity of yoga, many teachers take offense at what they feel is a trivialization of the ancient spiritual practice. They say that modern ways of doing yoga do not take into account the practice's origins in ancient India or the country's colonial history, adding that it is disrespectful of religious symbols that are inherent to the practice.

"While not captured in history books, yoga and sanskrit were stripped of their people in their own country under colonial rule. Yoga was a spiritual way of life for India and its people — not separate as a practice in a yoga studio," said Rina Deshpande, a yoga and mindfulness researcher, author and teacher.

A recent phrase that has come into use in this context is "cultural appropriation." According to Deshpande, cultural appropriation is about "reminding people to look at and acknowledge cultural roots and history" of practices originating with historically marginalized populations.

"It's not about telling people they're doing something wrong, rather it's bringing awareness to the foundation of yoga in India as a practice of wellbeing and spirituality with the physical postures [yogasana] being only one aspect of many, such as breathing techniques, philosophy, and meditation," she said,

"This way, the practice of yoga being offered to everyone can be as authentic as possible, honoring what it was holistically designed for," she added. 

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Deshpande has several examples which illustrate how cultural symbols are being misused, or at the very least, superficially used by consumers around the world. She feels that the practice has been heavily marketed as a great fitness and stress-relieving practice across the world.

Moreover, in the West, yoga is also advertised as something that requires material things such as expensive island retreats, or brand-name yoga clothing and equipment.  

"An example of cultural appropriation in yoga is printing Sanskrit on T-shirts or getting tattoos without being fully aware of what the words mean and the history of the practice," she said. For her, it is important to honor yoga's origins because of India's long history of oppression.

These issues have forced Bear Herbert, a yoga teacher in the US state of Louisiana, to forsake her yoga practice.

According to Herbert, cultural appropriation is about different cultures having different degrees of access to cultural practices because of their history of power and dominance. As a Caucasian person, she doesn't want to be offensive to other cultures.

In a blog post called "Beyond appropriation: A letter to my fellow white yoga teachers," Herbert said she "is deeply sorry for the ways my participation in white yoga culture has harmed Desi [Indian-origin] people."

Cultural appropriation or the curse of modernity?

Yoga professor Sanjay Singh feels that it would be unfair to relate yoga only to Hinduism or Indian spirituality, because it is more a way of life than just a physical routine.

"The theory of relativity is not a Jewish theory, just because Einstein was a Jew, and the law of gravity is not Christian because Isaac Newton was Christian. In the same way, yoga is about finding the truth. If you go down that path, you will know the real meaning of your life and get a glimpse of your real self," he argued.

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Meanwhile, yoga in India has also undergone many changes. According to Singh, 300 years of European colonization continue to have an impact on the country, and Western trends are sometimes considered to be better than Indian traditions. 

Thus, yoga is also a trend many Indians like to follow nowadays because it is fashionable in the West.

Additionally, Indians, like most global consumers, have been affected by advertisements that tout yoga as the perfect routine for a flexible, fit body and a relaxed mind. But above all, Singh stressed, it is important for practitioners anywhere to understand why they are doing yoga.

"If you are doing an asana and are fully dedicated towards doing it, if you are concentrating on it, and are fully present in the moment, that becomes yoga. Otherwise, it's just like swimming, running or any other sport," Singh said.