It's also offering all kinds of lessons on mind-body awareness." A lot of that awareness is focused on alignment, not outward perfection. And there's good reason for that. An aligned skeleton—in any posture—stimulates the energy channels in the body (known as nadis) and increases the flow of prana (life force) to the joints, skeleton, and muscles, which is said to keep you healthy. Yoga goes beyond asana, but it is asana, too.
"The ability to stretch a muscle is mainly limited by the nervous system's defensive reflexes. If you keep stretching a muscle after your protective reflexes kick in, the muscle will automatically contract and you'll tear it," Cole explains. "Part of the art of yoga is getting the nervous system to relax so that the muscles can let go." His advice is to relax, breathe, and perhaps even back off when you first feel the twinge that signals a limit. Relaxing instead of pushing might stop the muscle from contracting. Then, if all goes well, you'll eventually be able to stretch more without injuring yourself.