(from Level One Training and Fitness, November, 2012)

Those of you who train with me know how much emphasis I place on core work and working with the Suspension and Rip Trainers.  Some days are routine, other days you feel like you wished you stayed home in bed!  Be that as it may, your core continues to be perhaps one of the most important (if not THE most important) part of the  body you should always be working to strengthen.  The reasons for this should become quite evident by the time you finish reading.  We’ll begin with a few literal interpretations of “core” before transitioning into the world of exercise and fitness.  We’ll finish by running through a few good exercises you can do at home or even at work, if you’re feeling particularly motivated to keep your core in top shape.

Core what?

Without even getting into the muscles or the exercises, let’s start by asking: how do you define the word core?  In the most literal dictionary sense, a definition in dictionary.reference.com’s states: “the central, innermost, or most essential part of anything.”  Interestingly (from a fitness professional’s perspective, of course), the FIFTEENTH definition states: “the muscles of the torso, which provide support for the spine and pelvis: Building a strong core can help with posture and flexibility and can prevent back injury.”

There is a very good reason why “the muscles of the torso, which provide support for the spine and pelvis” was given the name “core.”  “It is the central, innermost, or most essential part” of your body when it comes to exercise and overall fitness.  Try to imagine walking upright if your abdominal or back muscles were weak or nonexistent.  What would happen?  Now imagine if you were trying to sit in a chair, run, walk, play sports, get into a car, even just get out of bed!

How many different planes of movement do you think are involved when trying to scale a 6 foot wall?

There’s “core” and then there’s life.

Whether you realize it or not, your core muscles greatly assist you in your day-to-day life, also known as activities of daily living or ADL. With a very weak core, life becomes quite burdensome. Among other things, your posture may suffer which in turn places unnecessary stress on certain muscles which in turn leads to aches and pains which may lead to over-the-counter pain relievers which may lead to…  get the picture? Worse yet for some, the aches and pains become a part of normal life; these people forget to notice the discomfort after a while. Their postural alignment may go out of whack, which leads to compression of nerves in the back, which can then worsen into degenerative conditions. Your core is central to you and your movement.

Now that we’ve established the importance of your core, let’s talk about life in three dimensions. Don’t worry, we’re not going to get too carried away with physics here, but we are going to talk terminology.  Your body moves in three planes, the sagittal, frontal, and transverse planes (Figure 1).  Movement can take place in few as one or as many as all three planes.

Sagittal Plane

Imagine a sheet of paper splitting you down the middle of your body into left and right halves.  Any movement that takes places parallel to the sheet of paper is considered sagittal plane movement.  This includes bending forward and backward from the hip, bending your knee up, and nodding your head.

Frontal Plane

Imagine a sheet of paper splitting you down the middle of your body into front and back halves.  Any movement that takes places parallel to the sheet of paper is considered frontal plane movement.  This includes bending to the left and the right from the hip, extending your legs out side to side, and tilting your head left and right.

Transverse Plane

Imagine a sheet of paper splitting you in half at the waist into top and bottom halves.  Any movement that takes places parallel to the sheet of paper is considered transverse plane movement.  This includes twisting your body to the left and the right from the hip, turning your leg in or out, and turning your head to the left and right.

Figure 1

While I mentioned only three different movements for each of the planes, it should be noted that any movement you make (right down to your fingers and toes) involves at least one of the planes. Movements that include your arms and legs or just standing or sitting upright, have their origin in your core. Without a strong core, you’ll run into a multitude of problems with these as well as the examples above (walking, running, playing sports, getting out of bed).

6-packs, 8-packs, and More

When you mention the word core, people instantly think of their abdominals and perhaps the muscles in their lower backs. Actually,  your core is comprised of many more muscles than that. The National Strength and Conditioning Association (NSCA) identifies the following muscles as your core:  rectus abdominis, internal oblique, external oblique, erector spinae, latissimus dorsi, transverse abdominis, iliocostalis, and multifidus (Figures 2 and 3).  As you can see, the core consists of more than just the ever-elusive “6-pack” or rectus abdominus.

Figure 2

Figure 3

If you take a look at the images, you’ll see that the muscles of the core run up and down, diagonally, and across your body. You’ll also notice that many muscles cross over from the left to the right and from the front to the back of your body. The combination of these muscles allows you to rotate your body, to swing a bat, turn your legs to get out of your car, and they allow you to do crunches. You use your core muscles for virtually every single movement and even to sit or stand still. Good core strength will allow you to handle your ADL as well as the things you do less often.

Exercises To Get You Rock Solid

Now that you’ve got the basics covered, you’re ready to tackle a bunch of different exercises which can strengthen your core.  If you’ve never done these before, don’t be discouraged if you can only hold a plank for 10 seconds or if you can only do 10 crunches.  If there’s one thing my clients have noticed, it’s that core strength progresses quite rapidly from week to week. Stay focused and consistent!

  • Planks
  • Side planks
  • Bird dogs
  • Mountain climbers
  • Medicine ball twist
  • Core ball transfer
  • Reverse crunches
  • Crunches


  1. “Core.” Core. Dictionary.com, n.d. Web. 01 Nov. 2012. <http://dictionary.reference.com/browse/core>.
  2. “Core Strengthening Exercises.” Core Strengthening Exercises. Fischer Sports, n.d. Web. 01 Nov. 2012. <http://www.fischer-sports.com/news/core-strengthening-exercises/>.
  3. Downing, Rebekah. “Health and Wellness.” Beginner and Advanced Core Exercises. Vanderbilt University, n.d. Web. 01 Nov. 2012. <http://healthandwellness.vanderbilt.edu/>.
  4. “Functional Training Resource, Courses, Movement Screening, Core Stability, Rehabilitation and Functional Exercise Programmes – All from Physical Solutions.” Understanding Planes and Axes of Movement. Physical Solutions, n.d. Web. 01 Nov. 2012. <http://www.physical-solutions.co.uk/index.php>.
  5. Merritt, April. “Planes of Motion.” Planes of Motion. ACE Fitness, 6 July 2009. Web. 01 Nov. 2012. <http://www.acefitness.org/blog/21/planes-of-motion>.
  6. “Muscles.” Spine Anatomy, Muscles and Ligaments, Ligaments. New York University Langone Medical Center, n.d. Web. 02 Nov. 2012. .
  7. Quelch, Fraser. “The Planar Training Method.” The Planar Training Method. Idea Health and Fitness Association, June 2007. Web. 01 Nov. 2012. <http://www.ideafit.com/fitness-library/planar-training-method>.
  8. Szelog, Matthew, ATC, CSCS. “Core Exercises: What Is the Core and How Do You Activate It?” Core Exercises: What Is the Core and How Do You Activate It? National Strength and Conditioning Association, n.d. Web. 01 Nov. 2012. <http://www.nsca.com/Education/E-learning/Core-Exercises–What-is-the-Core-and-How-do-you-Activate-it-/>.