McGill Big 3

First, What is Core Stability?

The core refers to a box-shaped body area comprising various muscle groups. These include the rectus abdominis at the front, the internal and external obliques on the sides, the erector spinae, lumbar multifidus, and quadratus lumborum at the back, the diaphragm at the top, the pelvic floor and iliac psoas at the bottom. In practical terms, the core muscles serve as the body’s center, where most kinetic chains transfer forces to the extremities. While many muscles are involved in the core, fitness and health professionals consider the transversus abdominis, lumbar multifidus, and quadratus lumborum the most crucial.

So, you have a weak core and are being told to do dynamic motions such as sit-ups, Russian twists, and back extensions, as these dynamic core exercises are traditionally used for strength training, relating to a stronger core. The notion that this will reduce your spine from buckling under load or reduce injury rate is a FALLACY.

Although, this may have truth behind it. The core muscles need strength and react to a load to stiffen them. However, here we are looking at the ability of all the muscles to “work together” to stiffen the core. Imagine a pop can for a second; a grown man can stand on an unopened pop can (where the forces are exerted outward 360degrees along the can wall) and the downward and upward force on the bottom and top of the can, respectively. If you were to open the can, the internal pressure would be released, resulting in the man crushing the pop can.

However, what most people and practitioners don’t understand is most people who develop back pain already have strong backs! So, although dynamic core exercises like sit-ups and Russian twists build strength, they do not help stiffen the core.

The second equation toward core exercises is looking at isometric core exercises. Isometric exercises have been shown to enhance stiffness, neuromuscular endurance, and coordination. Isometric exercises are performed by contracting the muscles without any joint movement or angle changes. This makes isometric exercises a pivotal strategy to enhance spinal stiffness and stability from a training standpoint and rehabilitation.

Enhancing spinal stiffness is essential when looking at lifting techniques (such as deadlifting or kettlebell swings), as the function of the core limits excess motions rather than creating them. So, for the core to build this massive stiffness of the spine, the muscles of the core need to contract all together synchronously. This creates the “natural weightlifting belt”.

McGill Big 3

Now that we know what types of exercise movement are best for creating spinal stiffness, we will discuss in detail how to perform the McGill Big 3. Keep in mind these exercises are not a one-size-fits-all. Instead, in Dr. Stuart McGill’s career, he found these movements to have the best impact of targeting the muscles with limited stress across the spine that have been injured or if you’re in pain.

Side plank Hip-Hinge

The side plank is a distinctive exercise that targets the lateral oblique and quadratus lumborum (QL) muscles on a single body side. This makes it an excellent choice for addressing stability weaknesses with minimal impact on the spine. Additionally, it activates a vital stabilizer of the hip/pelvis, namely the glute medius.

Here’s a step-by-step guide:

1. Begin by lying on your side with your legs bent and support your upper body on your elbow. Place your free hand on your opposite shoulder.
2. Lift your hips so your body weight is supported only by your knee and arm.
3. Hold this elevated position for 10 seconds before lowering back down. Repeat using a descending pyramid rep-scheme for each side.

North 40 PT Side Plank Hip-Hinge

To add variety and progression to the exercise:

• Experiment with different hand placements, such as moving from your opposite shoulder to the top of your hips.
• Gradually advance to a full side plank, where your body weight is supported by your feet and elbow.
• For an added challenge, perform the full side plank with one foot directly in front of the other.
• Take it further by incorporating a rolling pattern, where you tilt or rotate your body toward the ground and then back toward the ceiling during the side plank. Ensure your shoulders, torso, and upper leg remain straight to protect the lower back.

Bird Dog

This exercise is highly effective for enhancing core stability while simultaneously facilitating movement in the surrounding joints, such as the legs or arms and legs. The coordinated action of the hips and shoulders, with the lower back maintaining stability, translates well to daily activities and weight room exercises.

Here’s how to perform it:

1. Begin in a quadruped position, with your back in a neutral alignment. Remember that a slight arch, not complete flatness, constitutes a ‘neutral’ position.
2. Extend one leg backward without allowing any movement in the lower back while simultaneously raising the opposite arm until both are fully straightened. To prevent over-arching the back during the leg movement, focus on kicking the heel straight back. Contracting your arm muscles and making a fist while holding the extended position can increase core muscle engagement, particularly the erector spinae muscles. If performing arm and leg movements together is challenging or causes discomfort, try the modified version with only leg movement.

North 40 PT Bird Dog Exercise

1. Hold each extended pose for 10 seconds before returning to the starting quadruped position. You can also ‘sweep’ your arm and leg back underneath your body between repetitions. Maintain a neutral spine position throughout this motion, allowing movement only from the hips and shoulders. Repeat using the same descending rep-scheme as the previous exercises.

To progress:

• Challenge yourself by drawing a square with your outstretched hand alone or with your hand and opposite foot together.

Leg Curl/ Curl Up

Step 1: Begin by lying on your back with one knee bent and the other extended. Place your hands under your lower back to maintain a neutral, slightly arched spine for the next step.

Step 2: Elevate your head off the ground only a few inches, maintaining this position for 10 seconds. Be sure to keep your chin down towards your throat to avoid excessive accessory use of the sternocleidomastoid muscles (SCMs). The key is to execute this curl-up without any movement in the lower back. Raising your head and shoulders too high, akin to a traditional curl-up or crunch, can cause rounding in the lower back and transmit excessive force to the spine, potentially exacerbating symptoms.

Step 3: After the 10-second hold, gently lower your head back to the resting position.

North 40 PT Curl Up Core Strengthening

To progress and intensify the exercise, brace your abdominal muscles before moving your head or raise your elbows to reduce your stability base.

Dr. Josh Henderson added exercises to make it the Big 4

The last three exercises are derived from Stuart McGill’s Big 3. These exercises are great for honing in on the anterior and lateral chain core muscles with the Leg Curl and Side Plank Hip Hinge. Then, it takes advantage of performing rhythmic stabilization with extremity movements of the arms and legs with the Bird Dog, making this exercise a better rotary control of the spine.

Rotary control (or stabilization) can be defined as keeping the spine stiff and preventing spine rotation. This can transfer skills into shoveling, rolling in bed, and swinging (golf and baseball). However, another BIG muscle that needs to be addressed and synchronized with the core is the gluteus maximus (thinking as a unit, the entire posterior chain from the glutes and hamstrings).

Single Leg Bridge

The Single Leg Bridge is an excellent anti-rotation drill with the added benefit of extending the hips via the glutes and hamstrings. The leverage created by extending a leg out creates an external force load that the obliques and transverses abdominal muscles need to match to keep the pelvis level. Otherwise, what we see quite often is people performing this exercise with the pelvis dropped toward the floor on the side where the leg is extended out.

Step 1: Begin by lying on your back with your knees bent, as demonstrated.

Step 2: Initiate the movement by squeezing your buttock muscles FIRST, and lift your hips off the ground. Consider raising your toes and driving your heels into the ground to enhance glute activation. Maintain the bridge position while squeezing your glutes as forcefully as possible for 5 seconds before gently returning to the ground. If you experience hamstring cramping, adjust by bringing your heels closer to your hips. This shortens the hamstrings, placing them disadvantaged in contributing to the movement, a concept known as active insufficiency.

North 40 PT SL Bridge Exercise for Low Back Pain

Step 3: Once comfortable with the double leg bridge, progress to the Single Limb Support. After elevating your hips and engaging your glutes and core, extend one leg to level the thighs. Ensure your pelvis remains level, preventing it from dropping to the floor on the side where the leg is extended.

Recommended sets/reps: Start with two sets of 20, holding for 5 seconds each. Gradually increase to a 10-second hold as you progress.

Final Thoughts

These exercises are recommended to be performed daily while in pain. However, once out of pain, these exercises can be performed a few days weekly to build core stiffness while returning to daily activities or increasing weight at the gym. However, once out of pain, one should perform countless advanced core stiffness/stabilization drills throughout the week.

One of the most recent systematic reviews (which is the highest level of evidence to follow) by Oliva-Lozano and Muor (Oliva-Lozano JM, Muyor JM. Core Muscle Activity During Physical Fitness Exercises: A Systematic Review. Int J Environ Res Public Health. 2020 Jun 16;17(12):4306) found that the internal obliques (IO) was the greatest during core stability training, while the rectus abdominus, external oblique, and erector spinae muscles were the greatest during free weight strength training. The multifidus muscles demonstrated the highest activity during ‘traditional exercises,’ such as sit-ups and back extensions. The overall research lacked control studies for a conclusion on the transverses abdominus activation, which typically involves the draw-in maneuver in rehabilitation exercises.