What Your Core Is For


The primary purpose of your core is to support your spine during physical activity. Since your spine is a rickety, flexible rod – your core has a lot of work to do.

Your spine can move in many ways. Core musculature is designed to start, stop and stabilize each of the 7 ways your core is engaged.


Flexion is when you curl forward like in a crunch. This works your rectus abdominus – your 6 pack muscles. Strength in these muscles is important for both aesthetic and functional reasons.

From an aesthetic approach, flexion builds the ab muscles everyone envies. Brad Pitt’s early career was made by a strong, lean rectus abdominis. He achieved this look through diet (we’ll get to that) and focused, controlled, high frequency flexion.

From a functional standpoint, these muscles alleviate low back pain by bringing balance to your core musculature. Most of the day, the average person has their low back arched and tight. Strong abdominals will help counteract that tightness.

Extension is when you move from a bent over position to standing. The range of motion beyond standing up straight (neutral spine) is very minimal and frankly there is no need for extensive movement in this direction. In any range of motion, the burden of extension movements falls primarily to the two largest muscles in your low back, the spinal erectors.

Working your spinal erectors directly is important. Many cases of low back discomfort are due to the short, tight, underused spinal erectors. After stretching, implementing some direct low back strengthening in a well rounded core training approach can do miracles for daily back pain. 

Use a hyperextension machine to work the range of motion from flexed to neutral spine. This stretches and strengthens these chronically weak, tight muscles.

Anti-extension exercises build strength in the stabilizing muscles that counteract extension patterns. The rectus abdominis and transverse abdominis (deep core muscles used for stabilization), work together to keep your rib cage from flaring and your lumbar spine from arching.

Stress, chairs, and weakness tend to keep the average person in an extended spine posture for large parts of the day. The tension and pressure this creates the low back leads to varying degree or discomfort, pain, and sometimes more serious problems like sciatica.

Using the deadbug exercises and variations of the plank, muscular endurance is built over time using isometric holds. Please keep in mind that your spine needs to be in a neutral position during these exercises. Failure to maintain a neutral spine renders these exercises completely ineffective for the purpose you intend. If you’ve ever seen someone “planking” with a bend in their low back they’re not building strength in their core. Keep a flat spine to reap the benefits.

Lateral Flexion is bending your spine to the side (pulling your rib to your hip). Skip it. Lateral flexion has an incredible short range of motion and only does a mediocre job of working your obliques. In most cases people who attempt this use too much weight in too large a range of motion and only succeed in injuring themselves. Use the rotation and anti-rotation exercises to get far better results that direct lateral flexion could ever promise you.


Rotation (twisting to the left or right) works your obliques and can be done with or without resistance. Rotation is part of most everyday activities like walking, running, and turning.

Using cables and bands will help you keep strict focus and proper posture while building rotational strength. With two layers of obliques on each side you may feel rotation exercises on both sides at different points in the movement. One side will contract to start the rotation, the other side will contract to stop the rotation. 

If you play a rotational sport like golf, tennis, softball, or squash it is to your great benefit to exercise your rotational movement. Emphasize equal strength in both directions, not just your dominant side. Balance in your core strength will allow you to generate more power and reduce injury risk.

Anti-Rotation is the act of resisting rotation. Strength in this capacity will provide a foundation to rotate around. Twisting without a strong foundation is a lot like trying to fire a cannon from a canoe. Without solid land to fire from you generate less power and risk doing serious damage to the boat keeping you afloat.

Again for you who participate in rotational sports, your swing will be significantly weaker without this firm foundation.

Build anti-rotation strength using a cable or band to perform pallof presses. Always use slow, controlled movements to challenge your strength against rotation.

Arguably the most functional demand of your core is stabilizing you while you carry something. Whether it’s taking groceries in, holding a heavy purse or briefcase, or carrying boxes you are performing a variation of a loaded carry.

Strengthening your carrying stability is simple: pick up something heavy and carry it as far as you can with perfect posture. You can load this with dumbbells, kettlebells, sandbags, medicine balls, weighted vest, trap bars – the list is practically endless! Just pick up a heavy thing and go. 

This takes very low body fat percentages. Generally speaking, you’ll start to see some abdominal definition when men are below 9% body fat and women are below 19%. An individual may need to have even lower body fat depending on genetic factors.

This kind of leanness is achieved over months or years through strict nutrition practices and enforced with a rigorous exercise program. 


Training your core is best accomplished by doing one or two core exercises each workout. Your core recovers quickly so you can work it almost daily. Switch up the kind of movement you train day to day so you build a balanced core.

For example, for those of you who exercises 3 x wk:

Workout 1: One Flexion and one Anti-Rotation exercise
Workout 2: One Anti-Extension and one Rotation exercise
Workout 3: One Extension and one Loaded Carry

Next week rotate through those movements again.

There are some core issues that require customized approaches. If you have severely unbalanced core strength it can result in everything from mild discomfort to sharp sciatica pain.

There are also several acute reasons for core dysfunction. If you’ve had a baby recently and are experiencing diastasis recti your core training needs to be specific and monitored. If you’ve recently had a hernia or surgery to fix a hernia, you will need very specific meticulously coached core training. Some of these issues need to be dealt with by a licensed physical therapist, some can be coached by a corrective exercise specialist. 

Please don’t hesitate to reach out for more information about how to deal with pain or dysfunction of your core. We are here to help in whichever way is most beneficial to your recovery or progress.