Intro To Power Yoga by Yoga Zone. ''Power Yoga'' has gradually become the aerobics of the new millennium, driven by a no-pain-no-gain ethos that emphasizes sweat and strengthening over yoga's more subtle benefits. But this two-part, 40-minute Yoga Zone program takes a more mild approach, hewing to the philosophy that the power of power yoga depends less on aggressive, strenuous poses than on conscious awareness of oneself and the vital link between breath and movement. Both parts rely on brisk, flowing repetitions of several vinyasas (connected series of poses). The first includes some standing positions (mountain, warrior I and II, etc.), lunges, twists, side stretches, and the camel backbend. Those new to yoga will find the sequence alternating between the downward dog and plank positions to be fairly demanding, but there's nothing outrageously hard here. The second part again concentrates on the downward dog, one of the essential poses in yoga, along with twists, stretches (like the ''blown palm,'' a standing side stretch), forward bends, lunges and so on. The virtue of repeating vinyasas (i.e., moving in and out of several poses, one breath at a time) is that it reinforces proper breathing patterns, and the instructors do a good job of reminding you when to inhale and exhale.