The human spine is made up of three sections. The cervical spine, the thoracic spine and the lumbar spine.The lumbar spine refers to the lower back, where the spine curves inward toward the abdomen.The Lumbar spine is strong, built for power and flexibility. This curved lower area of the back meant for bending, lifting and twisting. The lower the vertebrae in the spinal column, the more weight it must bare. The vertebrae that make up this area of the back, L1-L5, are the biggest unfused vertebrae in the spinal column allowing them to support the full weight of the upper body. The two lowest parts of the Lumbar spine, (L4-L5) and (L5-S1) where the Lumbar spine meets the sacrum, otherwise known as the lumbosacral joint, bare the most of the body's weight and are therefore more prone to injury. In this article we will identify causes of low back pain and exercise benefits of the back.