What Is the Rectus Abdominis?

Rectus abdominis is located on both sides of the midline of the anterior abdominal wall and is embedded in the rectus abdomen sheath. The lower part is separated by 3 to 4 transverse tendons (compact connective tissue cords). The tendons are tightly healed with the anterior wall of the rectus sheath and play a role in preventing the muscle from shifting when contracted. The upper end of this muscle starts from the anterior side of the 5th to 7th rib cartilage and the sternal process of the sternum and ends at the upper edge of the pubic bone (between the pubic nodules and the pubic bone).

Rectus abdominis is located on both sides of the midline of the anterior abdominal wall and is embedded in the rectus abdomen sheath. The lower part is separated by 3 to 4 transverse tendons (compact connective tissue cords). The tendons are tightly healed with the anterior wall of the rectus sheath and play a role in preventing the muscle from shifting when contracted. The upper end of this muscle starts from the anterior side of the 5th to 7th rib cartilage and the sternal process of the sternum and ends at the upper edge of the pubic bone (between the pubic nodules and the pubic bone).

During lower fixation, both sides of the muscles contract the spine forward, and one side contracts the spine. During upper fixation, both sides contract to make the pelvis lean back. In addition, the muscle also maintains abdominal pressure, assists breathing, defecation, and childbirth.

Exercises such as sit-ups, sit-ups, and right-angle support can develop this muscle strength.

The muscular abdomen gradually widens backwards to the widest part of the abdomen. It runs in the rectus abdominis sheath, the posterior part gradually narrows and stops at the pubic nodules and pubic condyles with anterior tendon of the pubic bone.

Chinese name

Rectus abdominis

Foreign name

rectus abdominis

lie in

Anterior ventral wall on both sides of the midline, in the sheath of rectus abdominis

Attributes

muscle

Rectus abdominis related tissue structure

1. The blood supply of the skin of the abdominal wall The upper and middle skin blood supply of the anterior abdominal wall is mainly the perforating branches of the superior and inferior arteries; the lower part is the superficial blood vessels in the groin area, including the superficial abdominal wall arteries, superficial iliac arteries, and superficial external genital arteries Branch. These arterial branches coincide with each other, and there are more perforating branches of the myocutaneous artery with a large diameter near the umbilicus, and there are more perforating branches in the upper and middle parts than in the lower part.

2. The nerves of rectus abdominis innervate the nerves of segmental abdomen. The nerves that innervate the rectus abdominis are the anterior branches of the T6 ~ LI spinal nerves. These nerves run between the internal oblique and transverse abdominis in the anterior lateral wall of the abdomen, form a plexus before entering the rectus abdominis sheath, and then pass through the abdomen. Behind the muscle, often enter the muscle at the 13 / junction of the rectus abdominis.

Rectus Abdominal Training Method

The electromyography of rectus abdominis muscles showed a certain regularity during abdominal exercises. Take sit-up exercises as an example. At the beginning of the exercise, more obvious EMG activity occurs. When the upper body flexes forward to an angle of 40 to 60 degrees, the EMG amplitude and frequency are displayed, and the average integral chart amplitude is the largest, and the muscle tension is also the largest. . This angle is the most effective angle to increase the strength of the abdominal muscles.

Starting from the development of rectus abdominis muscles, knee-up sit-ups are better than straight-leg sit-ups.

Different developments of abdominal exercises have specific effects on the rectus abdominis muscles. Sit-up exercises featuring far fixation are systematically performed to reduce the value of the proximal rectus abdominis muscle excitement diaphragm; The overhanging leg exercises, which are characterized by near-fixation, reduce the excitatory threshold of the rectus abdominis distal abdominal muscles; while the system performs supine right-angle sitting exercises, which reduces the closed value of the rectus abdominis near and distal abdominal muscles.

To develop the abdominal muscles by lifting the legs and abdomen, it is best to use the practice of draping to lift the abdomen or to tilt the body to lie on its back.

Rectus Abdominal Related Diseases and Treatment

The rectus abdominis mass can be divided into inflammatory lesions, tumor-like lesions and tumorous lesions. Inflammatory lesions include non-specific infections, specific infections, and focal myositis. Specific infections include tuberculous abscesses, Brucella abscesses, and parasitic abscesses. Tumor-like lesions include hematomas, endometriosis, and vascular malformations. Tumorous lesions include benign and malignant tumors. Benign tumors mainly include ligamentoid tumors, hemangiomas, lipomas, and vascular tumors; primary tumors are less common, mainly fibrous synovial sarcomas and acinar soft tissue sarcomas. Secondary diseases mainly include metastases, lymphomas, and leukemias, among which metastases can be formed by direct invasion, incisional metastasis, and systemic metastases.