Other exercises that can relieve sciatic pain are strengthening exercises. The most important group of muscles that have a great impact in the improvement of the sciatic pain is the abdominal group.
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.
There are four main abdominal muscle groups that combine to completely cover the internal organs:
- Transversus abdominus, which is the deepest muscle layer. Its main roles are to stabilize the trunk and maintain internal abdominal pressure;
- Rectus abdominus that goes from the ribs to the pubic bone ate the front of the pelvis. This muscle has the characteristic bumps or bulges, when contracting, that are commonly called the “six pack”. The main function of the rectus abdominus is to move the body between the ribcage and the pelvis.
- External oblique muscles that are on each side of the rectus abdominus. The external oblique muscles allow the trunk to twist, but to the opposite side of whichever external oblique is contacting. For example, the right external oblique contracts to turn the body to the left.
- Internal oblique muscles that flank the rectus abdominus 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 internal oblique and the right external oblique to contract together.
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.
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 abdominus to increase spine stability and protect against back injury or strain during movement or normal posture.
Transversus Abdominus strengthening
Transversus abdominus is the deepest of the abdominal muscles and wraps around the abdomen between the lower ribs and top of the pelvis, functioning like a corset. When transversus abdominus contracts the waist narrows slightly and the lower abdomen flattens. The function of the transversus abdominus is to stabilize the low back and pelvis before movement of the arms and/or legs occurs.
Mid or low back pain (for example, trauma, sciatic pain, lumbar herniation disc), abdominal injury/surgery and/or excessive lengthening due to pregnancy can cause a delay or absence in the anticipatory contraction of transversus abdominus. If this muscle contraction delay/absence is not corrected, this dysfunction will remain, even after your pain has subsided.
For that, you need to restore your recruitment patterns (order in which different muscles contract). The first step is to learn to isolate the muscle and train it to contract.
Recruitment Training for Transversus Abdominis (TrA)
To activate your Transversus Abdominus, all you need to do is “suck in” your belly about 25% to 50%. To know if you are activating the desired muscle, just place your index finger slightly inwards from the left and right hip bone. The hip bones are two bony prominences in front of the waist. Breathe in and on the breath out contract the transversus abdominus.
Hold the contraction for 3 - 5 seconds and then release and breathe throughout this exercise. Repeat the contraction and hold for 3 sets of 10 repetitions 3 - 4 times per day for 4 weeks.
Once you can easily recruit Transversus Abdominus you can progress to the following exercises.
Lying on your back with your knees and hips flexed:
- Slowly let your right knee move to the right, keep your low back and pelvis level. Return to the center and repeat with the left.
- Lift the right foot off the floor keeping the knee bent. Don’t hold your breath and don’t bulge your lower abdomen. Return the foot to the floor and repeat with the left foot.
- Lift the right foot off the floor and then straighten the leg only as far as you can control your core without lifting your lower back from the floor. Slowly bend the knee and return the foot to the floor. Repeat with the left leg.
- Lift the right foot off the floor and then the left foot off the floor. Alternate leg extensions, exert with exhalation, breathe in to rest or hold. As always, do the leg extensions as far as you can without lifting your lower back from the floor.
In side lying:
- Keep your ankles together and lift your top knee (only as high as you can control without breath holding), focus on turning your inner thigh outwards. Return your knee.
- Keep your ankles together, lift your top knee and then lift your ankle. Return your ankle and then your knee.
With all these exercises maintain the leg lift for 10 seconds, build to 3 sets of 10 repetitions before moving on.
Once you can activate the Transversus Abdominus, you can practice recruiting it in many different positions such as sitting, standing, squatting, lifting etc.
It is not uncommon for other muscles to co-contract in an attempt to compensate for a dysfunctional core. It is critical that you take the time to focus on your technique and achieve a correct contraction before moving on to any loading through the arms or legs. Watch for the following substitution strategies:
- Posterior tilting of the pelvis
- Bulging of the abdomen
- Depression of the rib cage
- Breath holding
- Fingertips being pressed out by a strong muscular contraction (internal oblique)
The final step is to remember to use this muscle during regular activities. Each time you get out of the chair, lift, bend or reach, the deep muscle system should be working with and for you. The goal is to help the brain remember to use the deep system and the more you use it, the less you will be likely to lose it.
Now, if you want to, you can go to the gym and train your abdominals. But be sure to ask your physical therapist about the type of abdominal exercises you can or cannot do. For example, for people with a lumbar herniated disc it is dangerous to do all kind of exercises that require a torsion movement of your back.
Other exercises that can reduce your lower back pain are strengthening of the gluteus and stretching of the iliac psoas. The stretching of the iliac psoas should be done at least three times per day with three sessions of thirty minutes each.