Abdominal muscles explained

The abdominal muscles are located between the ribs and the pelvis on the front of the body. The abdominal muscles support the trunk, allow movement, and hold organs in place by regulating internal abdominal pressure.

Consult with your doctor, physiotherapist, or sports physician for proper diagnosis and treatment of abdominal muscle injuries.

The four main abdominal muscle groups

The four main abdominal muscle groups that combine to completely cover the internal organs include:

• Transversus abdominis – the deepest muscle layer. Its main roles are to stabilize the trunk and maintain internal abdominal pressure.
• Rectus abdominis – slung between the ribs and the pubic bone at the front of the pelvis. When contracting, this muscle has the characteristic bumps or bulges that are commonly called ‘the six pack’. The main function of the rectus abdominis is to move the body between the ribcage and the pelvis.
• External oblique muscles – these are on each side of the rectus abdominis. The external oblique muscles allow the trunk to twist, but to the opposite side of whichever external oblique is contracting. For example, the right external oblique contracts to turn the body to the left.
• Internal oblique muscles – these flank the rectus abdominis and are located just inside the hipbones. They operate in the opposite way to the external oblique muscles. For example, twisting the trunk to the left requires the left side internal oblique and the right side external oblique to contract together.

Core muscles

Think of your core as a strong column that links the upper body and lower body together. Having a solid core creates a foundation for all activities. All our movements are powered by the torso – the abdominals and back work together to support the spine when we sit, stand, bend over, pick things up, exercise, and more.

Your core muscles are the muscles deep within the abdominals and back, attaching to the spine or pelvis. Some of these muscles include:

• Transversus abdominis
• Muscles of the pelvic floor
• Oblique muscles

Another muscle that is involved in moving the trunk is the multifidus. This is a deep back muscle that runs along the spine. It works together with the transversus abdominis to increase spine stability and protect against back injury or strain during movement or normal posture. Proper ‘core strengthening’ techniques, learned from a skilled allied health professional, can support the combined function of these muscle groups.

Effective abdominal exercises

When you decide to add some abdominal exercises to your exercise program, be careful about which ones you choose. A qualified fitness instructor can help you develop a safe, effective program. If you have a pre-existing injury or medical condition, consult an exercise physiologist or physiotherapist.

Incorporate exercises to train your core muscle group, rather than standard crunches that target separate muscles. Some effective abdominal muscle training methods include:

• Pilates – an exercise technique traditionally used by dancers for deep-body conditioning and injury rehabilitation.
• Stability ball – also known as a fitball, Swiss ball, or exercise ball. This is an extra-large, inflatable ball designed to improve balance while targeting specific muscle groups. You can use exercise balls in a variety of ways to challenge balance, stability, and torso strength.

Muscle strains

You can strain your abdominal muscles from overstretching or overuse. Prevention strategies include:

• Regular stretching
• Warming up prior to exercise
• Cooling down afterwards
• Keeping good form while playing sport

Where to get help

• Your doctor
• Doctor specializing in sports medicine
• Physiotherapist
• Exercise physiologist
• ESSA Exercise & Sports Science Australia Tel. (07) 3862 4122
• Sports Doctors Australia Tel. (02) 8116 9815
• Sports Medicine Australia – Victoria Tel. (03) 9674 8777

Things to remember

• The abdominal muscles support the trunk, allow movement, and hold organs in place by regulating internal abdominal pressure.
• The deep abdominal muscles, together with muscles in the back, make up your core muscles.
• Your core muscles help keep your body stable and balanced, and protect your spine.
• Muscle strains can be prevented by regular stretching, warming up prior to exercise, cooling down afterwards, and keeping good form while playing sport.