The "Words I use" series is unofficially branching out into "Expressions I use" because realistically, we tend to use words in combinations, not in isolation... which was an unintentionally meta way for me to introduce a post about how, in everyday life, we tend to use movements in combination too. I use words to guide movement so... it all comes together nicely for this word-and-movement nerd.
What started out as a flippant, jokey statement one day has turned into a recurring theme, and even become a part of my movement principles: "everything can be core work, if you want it to" has slowly become "everything should be core work". Here's why.
Does anyone remember when "functional training" was all the rage? Every trainer suddenly listed "functional training" under their specialities, which basically just meant they made people use battling ropes or do box jumps? It was circa 2017, if memory serves.
I remember watching sedentary, office-working individuals being made to push weighted sleds back and forth, practically folded over in the middle, head hanging between their arms, eyes shut, and wondering what on earth the application of that exercise (and form) was to their life. I mulled over the words "functional" and "fitness" and the phrase "fit for function", and wondered if anyone could tell me where the need to swing a weighted log fitted into that. I watched people who couldn't do step-ups without flopping over at the waist be made to jump on and off* boxes as high as their hips.
*jumping backwards off a raised surface carries a high risk of Achilles tendon injury, due to the risk of impact if the calves aren't strong enough to control the descent of the heels... for most of us, there is just no need to be jumping back off the box backwards, no justification for taking that risk
But I'm not actually here to rant about fitness fads.
[I'd also like to point out that one original idea for this post was a gratuitous rant about the cue "squeeze your core", which suggests a fundamental misunderstanding of the structure and function of the core - and, I would argue, a lack of precision with words - but I'm not in that sort of mood, thankfully.]
Let's start, then, by talking about what the core is.
Many people use "abs" and "core" interchangeably. Many fitness professionals will have expanded the definition to, correctly, include the muscles of the lumbar spine.
The core is far more than that, though: technically, it is everything that isn't a limb or your head; so, essentially, your trunk.
The very word "trunk" gives us a clue as to the function of the core: think of a tree, and the qualities of its components. Roots, to anchor into the ground (and seek nutrients and signals from the surroundings). Branches, to spread leaves wide into the sunlight. And a trunk, to connect the two and provide stability and support. The branches and the roots are useless without the connection between them, and that connection won't last long if it isn't stable enough (and flexible enough) to withstand the elements.
Needless to say, the core includes all the muscles of the trunk: the superficial abdominals, the deep abdominals, the little muscles around each vertebra, the big muscles running right down your back, all the muscles in between and around your ribs, but also your pelvic floor muscles, your glutes, and your diaphragm. In other words, it's not just the muscles you see, and it's not just the ones you can "squeeze" (and you certainly can't squeeze them all at once).
Simply put, any time your pelvis needs to be stabilised, you will be engaging core muscles - so any time you are standing, or sitting tall, on all fours, or even lying on your back and performing movement with your limbs, you can and should be using your core muscles. Ideally, this would happen automatically - that's the job of the deeper muscles, especially - but for many of us, it doesn't: our bodies have gotten used to switching off from time spent sitting, in supportive chairs, not needing to move.
And it's not just when your pelvis needs stabilising, either: any time you breathe, your diaphragm has to move - contract and relax - as do all the muscles around your rib cage. And anything that affects your rib cage, can affect your shoulder.
So, essentially, even just focussing on breathing is core work. Standing tall with a neutral pelvis is core work. Pressing anything overhead whilst maintaining a neutral spine is core work. Even the much-maligned bicep curl is core work if you're thinking about your posture and your breathing.
Of course, none of those exercises will give you a six-pack; the six-pack muscle is rectus abdominis, and that mostly flexes your spine (as in an abdominal crunch). So it's an important muscle, but it's definitely only a very small part of your core, and crunches should form only a very small part of your "core training".
Back to functional training, briefly... what do you need your core for? If I liked to play guard as a Brazilian jiu jitsu player, I would need to be good at lying on my back in a crunched position - so variations on abdominal crunches would be functional - but if I'm exercising to be healthy and strong, do I need my body to be particularly strong in a flexed spine position? Most likely, I'm looking to be able to lift and carry shopping and/or kids (not a personal issue for me, but a very real one for many of my clients!), do bits and pieces around the house and garden, maybe play a sport... activities I will mostly be doing on my feet, often whilst holding or manoeuvring an object (or person) in one hand, changing positions frequently. So I need to be making my core strong when I am on my feet, possibly with an object in one hand, moving through different positions, possibly on uneven or changing terrain. I also need to make sure my core is strong in these positions whilst allowing me to breathe - for obvious reasons, as well as some slightly less obvious reasons (losing the ability to breathe diaphragmatically results in us overusing muscles in the neck and shoulders to breathe, which can cause tension and pain).
So non-ab exercises can be core work, and ab exercises can be non-core work. The difference is in the intention: another joke-turned-true statement I often make is "You have to make those core muscles work, the exercise won't just do it for you". I don't mean that our bodies are lazy, that we are cheating, or anything derogatory like that. What I mean is that you have to want to stabilise your pelvis, you have to want to smoothe that breathing out, you have to want to knit those front ribs in towards each other. I can give you exercises that make those things happen all day every day, but if your body doesn't learn how to keep those core muscles engaged when you are focussing on something else, then all the time you spend in the gym is only making you better at spending more time in the gym. Which is fine if that's your goal; I never mind what you choose to do with your body and your time, as long as you know what choice you're making and why. But really... why wouldn't you want every exercise to be a core exercise?