I've read about the star exercise and tried this technique for generating chi energy, all I can say is my feet and hands buzz for about 5 minutes after I have done this yoga (Sometimes my whole body). I do not believe this is hyperventilization, but who knows, I would like to know what others experience trying this technique.
The technique (see visual)
Close your eyes arms and legs outstretched like a star. Left palm up, right palm down...actually just read the link it explain this much better http://www.meditation-techniques.net/meditations/starexercise.htm