The core is a very misunderstood part of the body in that it is commonly mistaken that a “6 pack of abs” is representative of core strength or stability.
What muscles make up the core?
The 6 pack abdominals are just one muscle, the rectus abdominis, which functions only for particular movements.
There often are imbalances in the core where some muscles are overdeveloped either from training specificity or compensation.
A very developed rectus abdominis without proper function fo the other muscles is pretty useless.
What is core stability?
True core stability is defined as the proper sequencing of multiple muscles together to stabilize the spine in various positions.
Neutral Core Stability
- There is neutral core stability, which is where an individual can control their torso in a straight position.
Rotary Core Stability
- Rotary stability, which is where an individual can control their spine during rotational or twisting movements.
Dynamic Core Stability
- Dynamic stability entails more complex movements with external factors such as weight, resistance, speed, and change of directions in multi-planar directions.
Functional Movement Systems Core Motor Control and Rotary Stability Tests
How to test core stability
There are formal tests that physical therapists use that can be administered which measure core function objectively and help to define asymmetries and imbalances. These are:
What causes core instability?
Deficits are seen across the board in average individuals all the way to elite athletes.
A big part of this prevalence of core deficiency and discrepancy in symmetry is due to the more sedentary lifestyles of the average individual today.
Even advanced athletes that spend 2+ hours a day training, the time doesn’t equate to the amount of volume spent sitting, driving, relying on technology and being in inopportune positions. This is why consistent training and revisiting the basics is important.
Does an unstable core cause back pain?
In the general population, most back pain cases are due to deficient core motor control.
In advanced athletes, many become so good at compensating, that they actually learn to use other parts of their body to complete movements, especially against resistance, as opposed to the proper muscles of their core.
Areas such as hip flexors, hamstrings, lumbar muscles, and groin muscles are some common muscle groups that can tend to overwork as compensation and result in nasty injuries, often derailing athletes from their training and competition plans.
What are good core exercises?
The following exercises are some very basic foundational concepts and movements, that when revisited, can act as preventive measures towards developing imbalances while also ensuring a proper foundation for more complex movements and demands.
These exercises are generally focusing more on neutral core stability, emphasizing a stable torso in one plane of movement. Going forward, more advanced variations will be discussed.
Start with elbows and knees on the ground.
- Raise feet off of the ground while maintaining alignment between the shoulders and hips. Think about a straight line from your ear to your shoulder and side of the hip.
- Squeezing your glutes together can help to stabilize the pelvis and avoid lumbar extension and sagging down.
- Keep looking straight ahead to ensure the neck is neutral as well.
The plank is one of the most basic and well-known core exercises out there BUT it is often completed with compensation.
Excessively rounded shoulders, low back extension and neck extension are compensatory movements used to brace the spine when proper sequencing of the core is deficient.
Thinking about drawing the belly button inward while squeezing the glutes together helps to stabilize the pelvis in this position.
Assume the same position as the plank modified except now straighten your legs so your toes are on the floor.
- Focus on the same concepts of drawing the belly button in, squeezing the glutes together and looking straight ahead while maintaining a straight line from your ear to shoulder, hip and heel.
- Planks can be performed as raises where you focus on the form, raise up, hold then back down.
Once the form and technique are mastered, you can then progress to holding the position for time while preventing form break down.
Side Plank (Modified)
Assume the position of being on your side, propped up onto your forearm.
- Bend the knees and bring your feet behind you so there is a straight line from your shoulder, to the hip and to the knee.
- Keep the elbow closer to under your armpit.
- Draw the belly button inward, squeeze the glutes and then lift up.
Side Plank Regular
Once the concepts for proper form are mastered in the modified position without compensation, progression to the regular side plank is next.
- Assume the same position as the modified plank except straighten the legs.
- Stack your feet and keep a straight line from your shoulder to the hip and ankle. Avoid rotating your top shoulder forward as compensation.
- Keep your head looking straight ahead. You should not look like a shrimp curled up but rather as straight as possible!
- Draw the belly button in and squeeze the glutes together while lifting up.
Eventually, progress to holding for time once the form is mastered. If you experience neck tension or shoulder discomfort, you may be compensating with those muscles in order to brace yourself.
Focus more on the cues described here to tap into the right muscle sequencing.
Supine Double Knee Raise
Start by lying on your back with the knees bent and arms at your side.
- Draw the belly button in and while maintaining the belly in position; slowly raise the legs up so your hips and knees are flexed at 90 degrees.
- Slowly return back down while preventing the low back from extending. The belly button should be drawn in the entire time.
- Squeezing a light ball or pillow between the knees can also be used to help engage the abdominals.
- Once the form is mastered, this can be done with a weighted ball between the knees or against a resistance band.
The supine double knees raise or “reverse crunch” is a very good pelvis and core resetting exercise.
This move is often used in the clinic to help patients with pelvic dysfunction. Very limited individuals sometimes need to start with more basic pelvic motor control exercises than this.
They also may require breathing retraining to help restore motor control of the diaphragm, as breathing and diaphragm engagement is part of proper core stability.
Quadruped Opposite Arm and Leg Lift (Bird Dog)
Assume the position of being on your hands and knees.
- Make sure your wrists are directly under your shoulders and your knees are directly under your hips. At the same time, lift your right arm and left leg straight out.
- Really focus on the hand and knee leaving the ground at the same time. Also, focus on bringing the arm and leg STRAIGHT out and not up towards the ceiling.
- Focus on keeping your torso straight while avoiding lumbar extension or rotation from the midline. If one hip dips down or rises up and you feel off-balance, slow the movement down to correct it.
- Repeat with the opposite arm and leg, alternating sides, making sure to reset between each repetition. The SLOWER you move with this, the greater the benefit. This movement is all about coordination, not speed.
The “bird dog” exercise is one of the most poorly executed core movements seen out there. It is either performed too fast, with poor timing or with horrible form resulting in major back extension and rotation.
The amount of advanced athletes that cannot properly execute this movement is astounding!
When deficits are noted with this movement, it is dialed back to the very basics to ensure that the individual can express control of the pelvis and torso with a better foundation before adding accessory movement.
More basic progressions involve more time focused on hands and knees with breathing and pelvis movements only, eventually progressing into one arm or one leg moving.
Fun fact: If you look closely, you will notice this arm and leg lift actually mimics a single-leg stance with one leg straight and another bent.
Progressing from a quadruped position to a half-kneeling position then into a single leg stance is one-way core stability programs are properly developed in the clinic.
Individuals need to learn to control their core in more basic positions with minimal spinal load before progressing to more demanding positions.
Stand with your feet about shoulder-width apart.
- Holding a band in both hands with the other end tied around a post or bar, step out to the side until there is some resistance.
- Keeping the elbows in at your sides and hands at belly button height, press the band straight out. Keep the shoulders back and stay up tall.
- Avoid trying to round the shoulders and press forward with your chest muscles.
- While pressing the band out, resist the band from pulling your torso away from the midline.
- While staying tall, also focus on keeping your back straight and avoid arching your low back or sticking your butt out.
Focusing on drawing the belly button in and keeping the back straight will ensure proper pelvic position and avoid lumbar compensation.
Squeezing a ball or pillow between the knees can also help to generate proper sequencing of the pelvic and core muscles while pressing out. Practice this move while facing both directions.
To advance this movement, press the band out and try to step to the side into more resistance from the band while maintaining proper form. Then step back with the resistance decreasing without losing form.
Where and how often should I do these core exercises?
Core exercises should be performed 2-3 days a week
These exercises are simple enough to do in the home and are convenient especially for those with busy schedules.
Foundational movements such as these also do not require advanced equipment, which is also another convenience factor. As you can see, these are easily demonstrated in a corner of my basement.
The bottom line on core strengthening exercises
To review, these exercises are basic building blocks that the average individual and even advanced athlete can add to their training program to ensure a reduction in compensation and a sound foundation for core engagement.
These exercises are just a handful of examples, as there are many more involving the same concepts. This is a good place to start though, as going forward, more advanced progressions of these movements will be discussed.
In the clinic, with very poorly conditioning or inured individuals, even more basic variations are prescribed.
With social media and the buzz around high-intensity workouts being shared, it is very easy to want to do the crazy advanced and cool looking movements but this is where most individuals get into trouble because they are often skipping the building blocks required to properly execute these advanced movements.
The basics go a long way!
Remember, a fancy house built on a poor foundation won't last very long!
About The Author:
Michael St. George, PT, DPT (@icore_stgeorge on Instagram) is a physical therapist who works for Excel Physical Therapy and Fitness, which is a private practice that is based around the greater Philadelphia region and suburbs. He is FMS, SFMA, Y Balance, and Motor Control Test Certified with eight years of experience in outpatient orthopedics and sports medicine. His training consists of experience working with physicians and surgeons from the Rothman Institute and therapists in his field specializing in various manual techniques and advanced treatment procedures.