Rabb Gutman Locks who he himself studied in India under gurus, eventually becoming a guru himself with many followers discusses the dangers of these practices.
His story :
From Mystical Paths - Rabbi Gutman Locks:
Chi Kung and Tai Chi are more than simple movement meditation techniques. For instance, Tai Chi is almost always associated with Taoism. Taoism is an Eastern religion, which from its earliest roots writes of "ghosts, and deities, and wives of deities…immortals [i] "and of 'god.'" [ii] Taoism is a "reinterpretation of an ancient unnamed tradition of nature worship, divination[iii], and magic." [iv]
Can these practices be taught in a kosher way?
Even if your student only touches his toes and dances, if you tell him that he is practicing Chi Kung, or Tai Chi - or any other practice that is rooted in a religion other than the Torah - you are endangering his soul.
Beside the immediate spiritual intrusion that automatically occurs from practicing these aspects of foreign religions, students will often want to learn more about their new exercise system. They then buy books, visit Web sites, and put pictures on their walls. Then, when they move to another town, they find an "authentic" Oriental teacher. The result is that that Jewish student will soon believe in the spiritual teachings that accompany the exercises. Those names and roots are taken from Buddhism, and the Tao, and on and on.
Again, and to reiterate most clearly, any practice that is entirely physical with absolutely no association with other religions is assumed to be perfectly alright. However, the minute you include even a slight reference or association to those other religions, you are endangering your spiritual life.
Remember, there are many perfectly fine, non-spiritual systems available. There is no reason to look to the ways of the East.