What is "the Core"?

Ever wonder why your fitness coach is always telling you to use your core? Read on for some expert tips, you're welcome!

“Engage your core!”, “tighten your core”, "squeeze your core"... these are phrases we hear all the time from health and fitness professionals, but what exactly do they mean? What is "the Core" anyway? Let me get one thing straight, the core is not the 6 pack muscles that you see on Gerard Butler in the movie 300. The inner core is a group of muscles consisting of the diaphragm, pelvic floor, transverse abdominis and the multifidi that work together to stabilize our spine and prepare us for movement. These muscles anchor our outer core muscles: our rectus abdominis, lats, adductors, and glutes. The outer core generates power from the stability of our inner core.

Let’s take a closer look at our inner core. I will use a beer can for an analogy (Muskoka Brewery Detour is my beer of choice!):

  • The diaphragm (top of the can) is our muscle of respiration, which descends when we breathe in and elevates when we breathe out.
  • The pelvic floor (bottom of the can) consists of 4 muscles which support our organs and abdominal contents.
  • The transverse abdominis (front of the can) is a synergist to the pelvic floor, meaning that these muscles work together to counter the downward pressure from the diaphragm.
  • The multifidi (back of the can) supports and stabilizes the spine.

So how do these muscles work together? When we take a deep breath in, our diaphragm descends, which increases our intrabdominal pressure and puts our pelvic floor muscles and transverse abdominis on stretch (like stretching an elastic, known as an eccentric contraction). When we exhale, the built up elastic energy from the pelvic floor and transverse abdominis is released (the elastic recoils, known as a concentric contraction) and prepares us for movement.

Our breath is key to optimizing the inner core. When I tell patients to “engage the core” what I mean is: take a deep breath in, exhale fully through pursed lips (like you are blowing out candles), and then complete the challenging part of your exercise. Breath holding when exercising, or over exercising the rectus abdomins, can impact the effectiveness of the inner core muscles. Dysfunctional breathing patterns can cause incontinence, prolapse, pelvic pain, constipation, and so on. If you experience any of these symptoms, I recommend an assessment with a Pelvic Health Physiotherapist.

Want to learn more about the core and your breath? Stay tuned for Core exercise videos! In the mean time, I hope you will think about your breath when completing your exercises with the Nadora bands for better core activation. 

- Andi

Registered Physiotherapist and Kinesiologist


  • Jenna

    Love all of this ! Super helpful and interesting facts ! I can’t wait to put this all to use when I receive my bands!!

  • Julie

    Interesting! When you break it down like that, it makes sense how important our breathing pattern is during exercise. Thanks Andi!

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