The Internal And External Obliques

In this blog, we examine the external and internal obliques, named after the Latin obliquus, meaning diagonal or slanted. When a personal trainer sets exercises that involve rotational movement of the torso, it helps train the internal and external oblique muscles.

THE ORIGINATION AND INSERTION OF THE INTERNAL OBLIQUES

The internal obliques are found deep in the abdominal wall and originate from the iliac crest, the lateral two-thirds of the inguinal ligament and a sheet of connective tissue in the lower part of the back, known as the thoracolumbar fascia. They insert into the lower three or four ribs and the linea alba via aponeurosis.

THE ORIGINATION AND INSERTION OF THE EXTERNAL OBLIQUES

Located on the side of the trunk, the external oblique is one of the outermost abdominal muscles, originating from the lower eight ribs. The exterior obliques insert into the anterior half of the iliac crest and also into an abdominal aponeurosis – this terminates in the linea alba, which is a tendinous band that extends from the sternum downwards.

THE ACTION OF THE OBLIQUES

The obliques have the following actions:

• Compressing the abdomen by pulling the chest downwards
• Helping to support the abdominal viscera against gravity’s pull
• Providing stability and mobility when bending and rotating, whether standing, walking or running

A personal trainer can easily incorporate all these actions into an exercise programme.

The basic functional movement of the obliques encompasses any digging or raking action, as well as twisting and reaching for objects, whether seated or standing.

COMMON EXERCISES FOR THE OBLIQUES

Because they are part of the muscles that make up the core, the obliques should not be overused, for example, by sitting with a slumped posture, as this can affect the support of the spine.

Many clients may focus on training the rectus abdominis to achieve a six-pack; however, fitness professionals should also guide their clients through exercises that target the obliques to help strengthen and stabilise the core. Although strong obliques may not be visible, they can improve overall health and enhance training by enabling a client to lift heavier weights during resistance training.

Strengthening exercises include:

• Side bends
• Oblique crunches
• Reverse trunk twists
• Hanging leg raises
• Seated barbell twists

A personal trainer can also show clients how to perform some useful side stretches using the obliques; these can help improve flexibility and range of motion.

WHICH SPORTS USE THE OBLIQUES?

Training the obliques can help a fitness professional’s clients who are involved in sports or athletic activities such as:

• Rugby and other contact sports
• Golf and tennis
• Javelin, shot put and pole vault
• Gymnastics and rowing

PROBLEMS ARISING FROM WEAK OBLIQUE MUSCLES

Because abdominal strength contributes to the stability of the lower spine, it’s important to have strong oblique muscles to avoid injury to this area.

A personal trainer should include exercises to strengthen the interior and exterior obliques in a client’s training routine, as well as those for the more obvious abdominal muscles.