Abdominal Muscles: What to Know

Medically Reviewed by Dany Paul Baby, MD on August 25, 2022
5 min read

Your abdominal muscles surround your trunk between the rib cage and pelvis and keep your abdominal organs safe. Your core abdominal muscles also support your trunk and allow movements while keeping your body stable and balanced. Abdominal muscles exercises will strengthen them and protect your spine from injury. The different types of abdominal muscles and the back muscles keep your trunk stable and balanced. Knowing about these important muscles and taking care of them will serve you well.

Five muscles surround the abdomen. The wall of the abdomen is partly bone but mainly muscle. The muscles form a flexible but firm wall to keep the abdominal organs safe from injury and help them maintain their positions in the erect posture.

Interesting facts about abdominal muscles:

  • When people think of "six-pack abs," this only refers to the rectus abdominis which contracts to form those coveted bumps and ridges on the abdomen. However, the bumps are visible because of low belly fat and not necessarily because the rectus abdominis is especially strong.
  • Abdominal muscles are used for almost every activity, from breathing to biking. Even when the body is fully at rest, core muscles work together to keep the body in place. 

The abdominal muscles coordinate to move the trunk from side to side. They also maintain the abdominal pressure to keep organs in place.

The abdominal muscles help you breathe, too. Contraction of these muscles pushes the abdominal contents upward, applying pressure on the diaphragm. The same action helps in vomiting and coughing.

Abdominal muscles maintain a uniform pressure inside the abdomen. This helps the stomach, intestines, pancreas, liver, and other organs hold their positions. By contracting, your abdominal muscles can increase the pressure inside your abdomen. In this way, they help pass urine and stool and are used in childbirth.

Abdominal muscles are also needed to maintain posture and support your spine. 

Rectus abdominis. This pair of muscles lies in front of the abdomen. They arise from the fifth, sixth, and seventh ribs and attach to the pubic bone. These muscles have three horizontal tendons running across their front. These bumps give the "six-pack" appearance.

External oblique. Also known as the obliquus externus abdominis, this muscle arises from the lower eight ribs and attaches to the hip bone. You have two of these muscles, one on each side. These are the outermost muscles of the abdominal wall and help you turn your trunk from side to side.

Internal obliques. Also known as the obliquus internus abdominis, these are paired muscles lying on either side of the abdomen. They lie deeper than the external obliques but outside the transversus abdominis. They arise from the hip bone and attach to the lower six ribs. Along with your external oblique muscles, they enable you to twist and turn your trunk.

Transversus abdominis. This is the deepest of the abdominal muscles. It arises from the lower six ribs and the hip bone and attaches to the pubic crest.

Pyramidalis. This vertical muscle arises from the pubic bone and attaches to the linea alba, a structure between the two rectus abdominis muscles. The pyramidalis lies in front of the rectus abdominis and contributes to maintaining abdominal pressure.  

The abdominal muscles consist of three flat muscles (two obliques and the transversus) and two vertical muscles (the rectus abdominis and pyramidalis). Together, they form the abdominal wall between the bony ribs and the pelvis. They provide structure and strength to the front and sides of your abdomen. 

With the muscles of the back, these muscles form your core. Your core muscles keep your body stable and protect your spine during movements. In addition, core muscles work with your diaphragm to facilitate breathing and maintain pressure to keep your organs in place. 

Abdominal muscle injuries make trunk movements difficult. You may feel:

  • Muscle spasms
  • Difficulty moving your trunk
  • Pain in your trunk when you laugh, exercise, sneeze, or cough
  • Pain while breathing
  • Swelling or bruising over the affected muscle

These are usually signs of muscle strain. Rest is helpful to relieve discomfort and allow muscle strains to repair. If you experience severe pain in your abdominal muscles, consult a healthcare provider.

Muscle strains. Strains or pulls are common problems affecting your abdominal muscles. These usually result from:

  • Quick, strenuous twisting of your trunk
  • Overuse of the abdominal muscles
  • Overstretching of the muscles

Treatment of muscle strains involves:

  • Ice packs or heat application
  • Rest for the muscles
  • Gentle stretches without causing pain
  • Medicines to relieve pain and reduce swelling
  • Compression binders
  • Physical therapy after a few days

Hernia. A hernia is a bulging of abdominal contents, usually intestines, through a weakness or gap in the abdominal muscles. The bulge usually appears when you're straining or standing and subsides when you relax or lie down. The symptoms of a hernia are:

  • A bump or bulge that is more prominent when you are straining, coughing, or standing
  • Pain at the site of the bulge
  • Pain or bulging when lifting something heavy

Hernias can create dangerous situations like obstruction and strangulation, which need emergency surgery. A hernia will not go away on its own and cannot be cured by medicines. If you notice any bulge or swelling on your abdomen or groin, you should meet your doctor as soon as possible.

A hernia is repaired by surgery. Your surgeon will stitch any gap in your abdominal muscles after pushing the organs back into the abdomen. Sometimes, if your abdominal muscles are weak, they may place a mesh to strengthen the area.

Keeping your abdominal muscles strong is crucial to having a strong core. These muscles support your spine and pelvis when performing various movements. You should perform muscle-strengthening exercises at least two days a week and include exercises to strengthen your abdominal muscles:

Rectus exercise. Lie on the floor with knees bent and feet slightly apart. Put your hands on your thighs and slide them toward your knees, raising your head and shoulders off the ground. 

Obliques exercise. Lie on the floor as before. Raise your head and shoulders and try to touch your knee with the opposite hand. Repeat on the other side. 

Repeat these as often as you can without pain, and try to increase the number of repetitions as you get used to the exercises.

Pilates. This is a safe and effective exercise technique for strengthening your core. Pilates is used for injury rehabilitation, too. You should have an expert fitness trainer to guide you in including abdominal exercises in your fitness plan. It is important to perform warming up and stretching exercises before and cooling down after any exercise program.

Apart from exercising regularly, some other measures help to keep your abdominal muscles healthy and safe:

  • Be careful when lifting heavy objects.
  • Tighten your abdominal muscles when sneezing or coughing.
  • Eat a healthy diet with plenty of fruits and vegetables to prevent constipation.
  • Maintain healthy body weight.