Mumbai-based yoga instructor Asha Ambani doesn't sound surprised the ancient discipline is enjoying a surge in popularity on the mainland.

"For centuries, people in China and India have embraced the duality of one's spiritual and physical selves," she says. "Young Chinese people seem to connect with the physicality of yoga first, as it's representative of a 'cool' Western way of life. But what makes them return to their yoga mats is the deeper connection they develop with their spiritual side."

Yoga has become the latest in a series of exports from India to the mainland (after tear-jerk-ing soap operas and Bollywood-style dancing), having made its circuitous way there via the West. In Mumbai - as in all of India - yoga has evolved through myriad forms, and the hunt is on for something new and exciting.

On the mainland, however, the discipline is just getting started.

American Robyn Wexler, who has run the Yoga Yard studio in Beijing since 2002, says that during the first few years, almost all her students were expatriates or Chinese who had lived abroad. A decade later, at least half her students are locals.

"Life in Beijing has become commercial, competitive and consumer-oriented," she says. "Both the physical practices and the ethical precepts of the yoga tradition offer a welcome source of inspiration and balance for Chinese people of all ages."

Given that physical exercise of any form - including cycling on the streets of Beijing - is on the decline, yoga seems to be filling a gap.

Yoga is all about uniting the mind, body and spirit.

Wexler says she has found it easy to explain traditional yoga concepts to Chinese people as "there is a deep respect for and conceptual familiarity with such ideas as energy or qi, as well as an appreciation of the importance of maintaining a balanced physical and energetic state".

Perhaps the strongest indication that yoga has well and truly arrived in China came when the mainland's first formal training college for yoga instructors opened in Beijing in May. The Yogi Yoga Centre - which focuses on hatha yoga, a system that combines asanas (postures) with pranayama (breathing techniques) - is an offshoot of the Yogi Yoga Institute of China, which is run by Yin Yan, former editor in chief of Elle China, and her husband, Manmohan Singh Bhandari, a yoga expert from Rishikesh, a town in India's Uttarakhand state.

One of Wexler's students, Li Mi, 31, says she has learned a lot from Yoga Yard classes.

"They have helped make me more calm and even-minded," she says. "I used to be a much more anxious person. I would get irritated or upset easily. That has changed since I started practising yoga."