“Yoga is meant to be a nurturing form of exercise, not a rigid imitation of poses,” says Richard Faulds, author of the upcoming Kripalu Yoga: A Complete Guide to Practice On and Off the Mat. It’s very possible to stretch and strengthen your body without having to touch your nose to your knees or your feet to your head. Here’s how to help ensure that you leave yoga class serene, not sorry! Style Guide Look for styles with gentle yoga poses such as Kripalu, Viniyoga, or Integral Yoga. Bikram, Ashtanga, and Power Yoga are generally too vigorous for beginners and inflexible people. Teacher Training Find an experienced, certified yoga instructor who asks about your physical limitations and will modify pace or offer alternative yoga poses to meet your needs. To find a certified instructor in your area, go to the Yoga Alliance website, or call them toll-free at (877) 964-2255 (from the US) or (610) 777-7793 (from Canada). The Warm-up Ten minutes of easy movement will increase circulation, lubricate joints, and ready your body to stretch. Yoga poses should progress from simple to more difficult. X-rated Postures These poses can place tremendous strain on joints and disks: the plow, full shoulder stand, headstand, and full lotus. Beware! NEW from Prevention! Sculpt a strong, sexy core with Flat Belly Yoga DVD! Back Protection Keep knees slightly bent, and hinge from the hips when bending forward from standing positions. When arching backward in any pose, concentrate on opening the front of the body by lengthening from the navel to the sternum. Don’t overarch the lower back, which compresses lumbar disks. Knee-savers Don’t lock your knees in standing postures, despite what a teacher may say. If you feel any strain during sitting or kneeling yoga poses, place a cushion or folded blanket under your bottom. Neck Care Always keep your neck in alignment with the rest of your spine when arching backward. Don’t let it flop back or down. Your Limits Get to know your body and its injury-prone zones. Back off from any movement that causes pain or cramping. Don’t compare yourself with others. Hands On or Off Many teachers assist students during classes. In general, a light touch that brings your awareness to an area and allows you to make your own adjustments is safest. Teachers who adjust you by moving your body for you or forcing you into yoga poses may cause injuries. Just say no! More from Prevention: 5 Yoga Poses For Energy