Downward-Facing Dog - Adho Muhka Svanasana
A yoga basic. This pose works everything. When I first started yoga, I could get into the pose but could not hold it for very long. It is now easier for me to achieve the pose as I get lighter in weight, stronger in muscle, and more flexible in the joints.
You start on your hands and knees. Tuck your toes under and push up. Your body forms a 90 degree angle, more or less. Ideally, you push on your hands to push your hips back so your heels will go to the floor. It took me over three years to get my heels down to the floor. You are also working on length from arms through the torso to the waist. The head is neutral with neck long and relaxed. In other words, a really good stretch for the whole body.