What is the internal oblique?
The internal oblique is a deep muscle located in the abdominal region that helps with movements such as rotating the torso, flexing the trunk, and compressing the abdominal contents. It is one of the three muscles that make up the lateral abdominal wall, along with the external oblique and transversus abdominis. The internal oblique is located beneath the external oblique and runs in the opposite direction, with fibers running diagonally downward and medially.
Origin, insertion and function
Origin:
The origin of the internal oblique muscle is from the iliac crest, the inguinal ligament, and the thoracolumbar fascia. (1)
Insertion:
The insertion of the internal oblique muscle is to the linea alba, the pubis and the 10th to 12th ribs.
Function:
The function of the internal oblique muscle is to compress the abdominal contents, flex and rotate the trunk, and assist in laterally flexing the trunk. Additionally, it helps in exhalation by pulling the diaphragm up and supporting the spine.
![Internal Oblique muscles](https://upload.wikimedia.org/wikipedia/commons/2/2a/Gray395.png)
Common signs of weak internal obliques
Signs that your internal oblique muscles might be weak include:
- Lower back pain or discomfort
- Difficulty performing exercises that involve twisting or rotation of the trunk
- Poor posture, such as a swayback or a protruding belly
- Difficulty maintaining proper form during exercises that work the core, such as planks or side planks
- Difficulty performing daily activities that require trunk rotation, such as reaching for items on a high shelf or turning to look over your shoulder while driving
- Difficulty maintaining balance
- Increased risk of injury to the lower back and abdominal region
- Difficulty in exhalation
Exercises to strengthen the internal oblique muscles
These exercises can help you build stronger internal oblique muscles:
Russian Twist:
- Sit on the floor with your knees bent and your feet flat on the ground.
- Lean back slightly and raise your feet off the ground, balancing on your sit bones.
- Hold a weight or a medicine ball with both hands and extend your arms in front of your chest.
- Rotate your torso to the right, bringing the weight or ball to the outside of your right knee.
- Return to the center and repeat on the left side.
- Do 15-20 reps on each side.
Cable Woodchop:
- Stand facing a cable machine with a rope attachment.
- Grasp the rope with both hands and extend your arms in front of your chest.
- Step back to create tension on the cable.
- Rotate your torso to the right, bringing the rope across your body and down towards your left knee.
- Return to the starting position and repeat on the left side.
- Do 15-20 reps on each side.
Side Plank:
- Lie on your side with your feet together and prop yourself up on your elbow.
- Raise your hips off the ground, creating a straight line from your feet to your shoulders.
- Hold this position for 15-30 seconds and repeat on the other side.
Reverse Crunch:
- Lie on your back with your knees bent and your feet flat on the ground.
- Place your hands behind your head and lift your shoulders off the ground.
- Slowly bring your knees towards your chest, lifting your hips off the ground.
- Lower your hips back down and repeat for 15-20 reps.
Lying Side Bend:
- Lie on your back with your arms extended out to the side.
- Bring your right knee towards your chest and lift your head and shoulders off the ground.
- Reach your left arm up towards your knee.
- Lower your head and shoulders back down and repeat on the other side.
- Do 15-20 reps on each side.
It is always advisable to have a proper guidance and warm-up before attempting any exercise. If you have any doubts or concerns, please consult with a qualified fitness professional or physical therapist.
References:
- Flynn W, Vickerton P. Anatomy, Abdomen and Pelvis, Abdominal Wall. [Updated 2022 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK551649/