Five Things You Should Know About Your Core Exercise Program

Each evening after I put my kids to bed, I spend time searching the web for research, articles and blogs pertinent to women’s health and fitness. As my kids drift peacefully off to dreamland, I get more and more agitated at the misinformation that is being promoted on the web, particularly as it relates to Core exercise. Time to dispel some myths, right some serious information wrongs, and bring balance back to the force. 


  1. 1.The Core has four muscles. Not one, not 12, not 15, not 29 (how can you expect someone to exercise 29 muscles simultaneously when you ask them to “engage the Core”....?). The true Core, sometimes referred to as the inner Core unit, is comprised of the diaphragm, transversus abdominis, pelvic floor, and multifidus. These four muscles work together like gears in a machine to stabilize our physical center (the spine and pelvis) during exercise and as we go about our day. Creating this strong anchor gives the rest of the muscles of the body something sturdy to pull against. Only these four muscles are capable of performing this critical task, because they are the only muscles in the body that are designed to automatically activate to stabilize the center before any other muscle group turns on to create a movement. (1)


  1. 2. Core exercises should not be confused with trunk exercises. Because all things Core have become so watered down, any exercise that involves the trunk muscles (abdomen, back and buttocks) is now considered a Core exercise. The trunk muscles do have a strong relationship with the Core, their proper activation relies on them being rooted in a strong Core foundation. In order for an exercise that involves the other muscles of the trunk (29 muscles apparently...) to be a true Core exercise, the exercise progression would move from the inside-out. Core first, then engagement of the other trunk muscles. (1)


  1. 3. Just because your do the exercise on a stability ball or a Bosu does not make it a Core exercise. Seriously, people can cheat on any piece of exercise equipment, and stability balls and Bosus are no exception. If you are busy compensating (or cheating) with a bunch of trunk muscles because of poor form and no sense of how to really connect with those deep Core muscles, you will not receive any added benefit from being on top of a ball. (2)


  1. 4. All together now, say it with me...the pelvic floor is part of the Core. The oogy, “oh we can’t talk about that” factor surrounding the pelvic floor needs to move along with the piano tie, shoulder pads, and jazzercise. Our antiquated misgivings about discussing this group of muscles, b/c that is what they are...just muscles that happened to be geographically related to our vagina’s and penis’ (yes I went there)....needs to go. The pelvic floor is the powerhouse behind a really amazing Core. It is the secret ingredient to a flat belly, keeping backs and hips strong and pain free, and helping you have great sex. Seriously, who doesn’t want that! The pelvic floor must be incorporated into Core work, it is one of the gears in our Core machine. A machine with a missing gear, will not work well (or work for that matter). That Core machine will fail to provide the central stability you are seeking. (3, 4)


  1. 5. What does “Engage your Core” mean anyway? The common instruction given along with these “Core” exercises is to “engage your Core”. Considering the definition of which muscles make up the Core varies, how an exerciser interprets this command is prone to some subjectivity. Sometimes the “engage your Core” command is further defined with a follow-up instruction that is something like “pull belly button to spine,” “hollow your belly,” or “pull navel away from waistband.” In my experience, these cues meant to help folks activate the Core often cause folks to tuck their bums under and flatten their lower spines. Try it. Look in the mirror and watch what happens to your bum when you “hollow your belly” or “pull your navel to your spine”. In a bum tucked under/flattened low back position the Transverse Abdominis (your TA, and deepest abdominal) and pelvic floor are poorly activated. So when these exercise prompts are given, they actually reduce your Core muscle work, and force you to compensate with other trunk muscles. This will not only reduce your results, but also leave you vulnerable to injury. (5)


There is a lot of material on the Internet on women’s health and much of it solid. But in an era when anyone can post advice be sure to check the credentials and reputation of these “experts” (feel free to check mine). Just because they put up a buff picture on their website doesn’t mean they’re qualified to help you. And in some cases, they’re lack of qualifications can leave you in worse shape then when you started.




  1. 1. Hodges PW, and Richardson CA. 1997. "Feedforward contraction of transversus abdominis is not influenced by the direction of arm movement." Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale 114, no. 2: 362-370.


  1. 2. Mori, Rl, Bergsman AE, Holmes MJ, Yates BJ. 2001. “Role of the medial medullary reticular formation in relaying vestibular signals to the diaphragm and abdominal muscles.” Brain Research. May 25: 902 (1): 82-91. 


  1. 3. Hodges PW, Sapsford R, and Pengel LH. 2007. "Postural and respiratory functions of the pelvic floor muscles." Neurourology And Urodynamics 26, no. 3: 362-371.


  1. 4. Sapsford, R.R., and P.W. Hodges. 2001. "Contraction of the pelvic floor muscles during abdominal maneuvers." Archives of Physical Medicine & Rehabilitation 82, no. 8: 1081-1088.


  1. 5. Sapsford RR, Hodges PW, Richardson CA, Cooper DH, Markwell SJ, and Jull GA. 2001. "Co-activation of the abdominal and pelvic floor muscles during voluntary exercises." Neurourology And Urodynamics 20, no. 1: 31-42.

Julie Wiebe Physiotherapist Interior Fitness Follow me @interiorfitness Blog:


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