Which Muscle Contracts Concentrically to Extend the Spine
Erector spinae allow vertebral rotation in the sagittal plane (e.B extension of the lumbar spine) and posterior vertebral translation when the muscles contract bilaterally. The multifidus muscle is also involved in lumbar stretching movements and is therefore a target of exercises to strengthen the lumbar spine. Stretching (or hyperextension) of the trunk is caused by the back muscles around the spine. These deep back muscles form a wide, thick spine that extends from the sacrum to the skull. The largest of these muscles is the erector spine. The origins and insertions of the different deep muscles of the back overlap considerably, and when they contract, entire regions of the spine can be moved at the same time (leading to prolongation or hyperextension). When these muscles contract only on one side of the spine, lateral flexion occurs. When lateral flexion occurs, there is a certain degree of rotation of the spine. In healthy people without back pain, the muscles of the erector spine relax in an area from the upright position to full lumbar flexion, because the deep muscles of the back (multifidus) stabilize the lumbar spine.
The human heart is the most incredible muscle in the body, beating about 100,000 times to send 3,600 gallons of blood through 75,000 miles of blood vessels every day. Sure, skeletal muscles are crucial to our ability to function, but the heart is really a notch higher. The iliocostalis muscles are the most lateral erector-spinae muscles. According to their attachments and location, they are regionally divided into three groups, from upper to lower: The erector spinae muscle, also known in some texts as sacrospinalis and extensor spinae, originates from the deep muscles of the back. It is superficially in the transverse-spiny muscle group and deep in the intermediate group of the back muscles (upper and lower posterior Serratus).   Abdominal muscles protect and support internal organs when properly trained. Other functions include lateral bending and hull rotation as well as forward bending against resistance (as in sit-ups or cracking). Erector spines are a group of muscles that work together to lengthen the spine and thus maintain good posture. The muscles are innervated by the spinal nerves. Rhomboids – these diamond-shaped muscles originate from the spinous extensions of the cervical and thoracic vertebrae (C7 to T5) and attach to the shoulder blade. The main action of rhomboids is to retract the shoulder blades (retraction of the scapula).
Bilateral contraction of the erector muscles causes an extension of the back and head. They are also involved in controlling the flexion of the spine.  The term paraspinal muscles is used to describe erector spinae and transversospinalis groups together. These muscles are the intrinsic muscles of the back that are so called because their embryological development begins in the back, unlike the superficial and mid-back muscles that develop elsewhere and are therefore classified as extrinsic muscles.  1.Group of thoracic erector spinae, i.e. Iliocostalis; Longissimus; Spinalis – the main muscle of the extensor muscle (leaning backwards) of the thoracic spine, which is located on both sides of the spine. Several ligaments hold the vertebrae together to make the spine more stable. Possible movements on the spine include bending, stretching, lateral flexion and rotation. The combination of bending, lateral flexion and hyperextension leads to circumnavigation. Movement is not uniform throughout the spine: in patients with back pain, the activity and atrophy of the multifidus muscle is reduced, which adversely affects the stability of the spine . The control of the spine is compensated by the increased activity of the erector muscle spinae to stabilize the lumbar spine.
 Back muscles can be divided into 3 categories based on their location: Latissimus dorsi muscles (also called lats) are the largest muscles in the back. Erector spinae consist of many muscles and attachments. Simplify your learning by focusing on the most important facts with Kenhub`s muscle anatomy and reference diagrams! The movement of the lumbar spine is carried out in 3 planes and includes 4 directions, as follows: Forward bending: 40-60 ° Extension: 20-35 ° Lateral flexion / lateral flexion (left and right): 15-20 ° 2. Transversospinalis group – these shorter, deeper muscles help stabilize the segments of the spine. The synergist would be the hip extenders (glutes) and the latisimus dorsi, which help the straighter spine to function. The joint action for a back extension consists in the fact that the spinal cord bends and therefore each bone of the spine is bent. The disc between each bone allows each bone to slide and move. Bend your head towards the opposite knee and take your other hand and put it behind your head and gently pull your head forward to stretch. Press and hold it for 5 seconds and repeat it 5 times. This simple stretch relieves tightness and pain in the cervical spine.
All flexors and extensors in the torso can produce lateral flexion when acting unilaterally. The main muscles involved are the rectus abdominis, the external and internal oblique, the erector spinae, the semispinalis thoracis, the latissimus dorsi, the deep posterior spinal muscles, the quadratus lumborum and the psoas. Many thoracic spine problems are related to poor posture and/or muscle irritation or tension, also known as myofascial pain. Muscle fascia Fascia is a thickened connective tissue that envelops a muscle or group of muscles. The superficial fascia is located just under the skin. Epimysium is the fascia closest to the muscle. Perimisium divides the muscle into facials – muscle fibers. Endomysium is another type of connective tissue that covers all muscle fibers. Strains consist of a certain tear or stretching of the muscle fibers. The muscles of the erector spines are most often affected by back loads.
Back loads are usually the result of a poor balancing of a load on the spine, which puts pressure on the muscles. Using the back as a lever when lifting objects puts immense pressure on the back muscles, which is why lifting should usually be focused on the knees. Muscle cramps as a protective mechanism after an injury. .