The paired skeletal muscles that enclose the abdominal and pelvic space and connect the chest with the pelvis are called the abdominal muscles . These muscles allow the torso to tilt and rotate and to adapt to changes in abdominal volume, such as growth during pregnancy. The simultaneous tension of all abdominal muscles increases the pressure in the abdomen and, acting as an abdominal press, increases either the exhalation or the excretion of feces and urine . The abdominal muscles are divided into three groups, the naming of which is not uniform.
The abdominal muscles are divided into three groups according to their location:
Front abdominal muscles:
- Rectus abdominis muscle (straight abdominal muscle)
- Pyramidalis muscle (pyramidal muscle )
Lateral abdominal muscles:
- Musculus externus abdominis (external oblique abdominal muscle)
- Musculus obliquus internus abdominis (internal oblique abdominal muscle)
- Transversus abdominis muscle (transverse abdominal muscle)
Posterior abdominal muscles:
- Quadratus lumborum muscle (square lumbar muscle)
- Iliopsoas (large lumbar muscle)
The groups can also be named differently: the rear abdominal wall muscles are then called the deep abdominal muscles, the lateral and front muscles are called the lateral and middle muscles of the superficial abdominal muscles.
The lateral abdominal muscles with their aponeuroses - that is, flat tendons - form the so-called rectus sheath , in which the straight abdominal muscle comes to rest.
The straight abdominal muscle is in the front, it can bend the upper body forward or lift the front edge of the pelvis. It is the direct opponent of the spinal muscles and counteracts the hollow back . Like the anterior thigh muscles , the glutes and the back muscles, they are among the muscles that are particularly important for people walking upright. Well-trained abdominal muscles facilitate good posture .
The two oblique abdominal muscles can tilt and turn the upper body to one side. The transverse abdominal muscle can produce an abdominal crunch, e.g. B. when defecating . The abdominal muscles are also auxiliary muscles during exhalation .
There are two natural openings in the muscles of the abdominal wall:
- Franz-Viktor Salomon: musculoskeletal system. In: Franz-Viktor Salomon u. a. (Ed.): Anatomy for veterinary medicine . Enke-Verlag, Stuttgart 2004, ISBN 3-8304-1007-7 , pp. 22-234.
- Werner Platzer: Pocket Atlas of Anatomy, Volume 1 - Musculoskeletal System . Thieme Verlag, Stuttgart 2005, ISBN 3-13-492009-3 , p. 124.
- Gerhard Aumüller u. a .: Dual series anatomy. Georg Thieme Verlag, Stuttgart 2010, ISBN 978-3-13-136042-7 .
- ↑ Abdominal and core muscle training: A strong core prevents postural damage ( Memento from January 20, 2012 in the Internet Archive )