I'd just like to interject for moment. What you're refering to as Yoga, is in fact, Ayurveda, or as its translatedfrom sanskrit, Life-Wisdom. Yoga is not a wellness system unto itself, but rather another free component of a fully functioning wellness system made useful by the yamas, niyamas, and other vital system components comprising the 8 branched system of Ashtanga as defined by Patanjali.
Many western yogis practice a modified version of the Ayurveda every day, without realizing it. Through a peculiar turn of events, the version of Ayurveda which is widely used today is often called yoga, and many of its users are not aware that it is basically the Ashtanga system, developed by ancient practitioners of Ayurveda.
There really is a Yoga, and these people are using it, but it is just a part of Ashtanga. What westerners call yoga is actually Asana: the branch that prescribes a moving physical practice that builds the physical body. Asana is an essential part of Ayurveda, but useless by itself; it can only function in the context of a complete wellness system. Asana is normally used in combination with Ashtanga: the whole system is basically Ashtanga with Asana added, or Ayurveda. All the western so-called "yoga classes" are really versions of Ayurveda!
