Understanding and Building Core Strength

Apr 11, 2019

By Jacob den Dulk, Gym Tech and Exercise Specialist, Robinet PT Greenville Clinic

Having a strong core means more than just having a ripped six pack.

Which muscle groups actually make up your core?

Core muscles span the distance between your rib cage to your pelvis and wrap around from the stomach to your back.

At Robinet Physical Therapy we like to think of the core as a box. Without each individual side of your core functioning properly, you can’t truly have a strong core as a whole.



Attaches across the thoracic cavity and controls breathing


Pelvic Floor Muscles

Give bladder and bowel control as well as support to the pelvic organs


Erector Spinae

Stabilizes the spine, controlling posture, and aids in some side bending activity


Rectus Abdominis

(Yes, the “six pack”) attaches from pubic bone to ribcage and controls tilt and control of pelvis


Transverse Abdominis

…as well as Internal and External Obliques – 3 different layers of muscles that run side to side as well as diagonally in both directions to allow for the twisting and rotation of the torso in all different directions

What happens when one of the core muscle groups isn’t functioning correctly?

Muscle weakness leads to imbalances and COMPENSATIONS!

Why does my back hurt after I do a core workout?

A lot of popular workout programs include “core exercises” that involve lifting your legs including: straight leg lifts, bicycles, frog kicks, jackknives. Any exercises involving your legs are usually just that, LEG EXERCISES. Not that these exercises can’t be performed, but they shouldn’t be performed by someone without an existing strong core. Lifting your leg is the primary action of your hip flexor muscles which attach to your lower back. Overworking them only creates further imbalance resulting in even worse back pain. Sound familiar?

So, where do I start?

The first step we like to start with is a simple pelvic tilt isometric contracting your lower abdominals.

  1. Lay on your back with your knees bent up and flatten your lower back to the floor by using only your lower abdominal muscles? (no cheating with your leg muscles).
  2. Did you hold your breath? Breathe! It is important that you can isometrically contract and hold your abdominals while still breathing normally. Remember when we talked about the diaphragm above? Your abdominal muscles should be able to function separately from your diaphragm. Practice this.

If you are having trouble doing this it could be a sign of some major muscle imbalances or muscle inhibition going on. If you have further questions, then schedule a free consultation. Let us help you figure which core muscles are functioning and which ones are not. Everyone is unique. We can point you in the right direction to get you feeling and being your best.

If you found this easy, then go ahead and progress to the pelvic tilt isometric with a slight head lift.

  1. From the same position laying on your back.
  2. Repeat the same step of flattening your lower back to the floor.
  3. Then with your hands behind your head lift your head and shoulders off the table as if lifting your nose straight to the ceiling by a string. No crunching or curling should occur. All motion should be created from the contraction of your lower abdominal muscles. Make sure that you are still breathing.

If you are able to complete that exercise without any issues or problems then go ahead and progress to other core exercises that involve lying on your back and moving your arms and legs.

Back to basics

Next time you are performing any core exercise ask yourself, “Am I able to flatten my back to the floor and maintain that position throughout the entire core exercise?” If not, then it’s time to get back to basics with the above exercises.