With a strong core you improve almost every yoga pose and the whole practice of yoga becomes much easier and safer. Your balance and ease in the practice will increase. On a spiritual level, when the core is strong, the ups and downs of our lives are much easier to take. We feel much more resilient.
When we work on the core in yoga we try and include the following muscles:
They attach the thighbone to the pelvis. These muscles draw the legs in towards each other (the mid-line).
2. The Rectus Abdominis, or RA
This muscle runs vertically from the middle of the rib cage in the front of the body to the pubic bone. Associated with the "six-pack" in Western society. This muscle activates when you do leg lifts, or Boat pose (Navasana).
3. The internal and external oblique abdominis muscles
These are more commonly known as the side muscles. They run at a diagonal along the flank of the body, attaching to the midline beneath the Rectus Abdominis. They keep the torso stable in poses like Triangle Pose, Half Moon Pose, and Side Angle Pose.
4. Transverse Abdominis or TA
Located below the obliques is the transverse abdominis (TA), a horizontal band of muscle that runs side-to-side from the rib cage to the pelvis and basically holds the contents of the abdomen in place. The transverse abdominis is related to Uddiyana Bandha.
5. The quadratus lumborum (QL)
This is a deep stabilizing muscle that connects the upper body with the lower body. This muscle plays a key role in good posture and influences the curvature of the spine. It runs vertically from the lower ribs to the pelvic crest. It plays a big role in side bends, and twisting poses.
6. Psoas Major (a hip flexor)
This muscle originates at the outside of the lumbar spine, runs across the pelvis along the inside of the pubic bone, and attaches to the inner thigh bone. A very deep, strong and large muscle that we use unconsciously, when we walk, sit, stand. We flex it in a forward bend and we extend it in a backbend.