The one universal cue used in regards to almost every exercise is “Use your core!”. I’d bet every single personal trainer and fitness class instructor has slipped this saying out at least once or twice. The cue is made out to seem so blatantly obvious and straight-forward on the surface, but in reality, it usually isn’t. Most people can’t even name a single core muscle by its true anatomical name (no, “ab” does not count), let alone have the ability to contract the right ones on demand.
Why this cue doesn’t really make sense
When you dive deeper into the words “use your core”, it actually doesn’t make a whole lot of sense in context. The core is made up of almost too many muscles to count and not all of them are responsible for the same actions. In fact, some muscles of the core directly oppose the actions of other core muscles (Example: some muscles contract to flex or resist extension of the spine and others contract to extend or resist flexion of the spine). Therefore, not every core muscle can be used at the same time. I get that it does sound a lot better to say “Don’t forget to use your core” instead of “Make sure you’re contracting your transverse abdominis, rectus abdominis and external & internal obliques!”. However, the true complexity behind the term is very misunderstood and is very overused considering the small amount of people that actually know what the true meaning behind the cue is.
What everyone usually means by “Use your core”
In the context of large compound exercises like squats, deadlifts, pull-ups and pressing, the cue is referencing one’s ability to stabilize the spine. The spine is stabilized by contracting muscles surrounding the thorax in order to resist movement and by creating pressure in the thorax via breathing and bracing. By stabilizing the spine, your brain will feel safer allowing the muscles of your limbs (the ones responsible for moving the load during the exercise at hand) to produce more force and, therefore, you’ll be stronger. A stable spine under heavy load is also of upmost importance for keeping those small joints that make up the spine safe and healthy.
More useful cues
As a trainer, I must have very many cues in my toolbelt to use for different clients doing different exercises under varying degrees of intensity. However, there are a handful of cues that I use with all my clients when teaching proper spine position and bracing.
When the ribcage is tilted upwards, the hinge point of that tilt comes from a segment at the spine. This tilting puts the spine in some degree of extension. One of the first things I go over with new clients is the ability to move the ribcage back to neutral and keep it there while the limbs move. Without fail, you’ll feel some core muscles shorten and “turn on” right away.
“Tuck your bum”
In the same way spinal position is controlled by the ribcage, the pelvis also determines how neutral the spine is or isn’t. I dove a little deeper into anterior pelvic tilt in this article and how it affects the muscles recruited when doing an exercise in that posture. When someone is tilting his/her pelvis anteriorly (to the front) and consequently arching the lower back, saying “tuck your bum” is my way of getting them to posteriorly tilt the pelvis back to neutral, ultimately getting the spine in better position so that the core is better able to do its job.
“Find your hamstrings”
Hamstrings are super underappreciated in core training. Having sufficient closing-angle hamstring strength will stabilize the pelvis better than any traditional core exercise in my opinion. When the hamstrings are incredibly weak in the shortened position (deep knee flexion or simultaneous hip extension and knee flexion), no amount of bracing and core strength can prevent the pelvis from anteriorly tilting when you’re forced into that position. A great example is a deep squat; if you dive-bomb and fall into the bottom of a squat when you don’t have the strength to generate enough hamstring tension to stabilize the pelvis, your pelvis will tilt to the front and your lower back muscles will have to kick on to pick up the slack.
“Breathe into your lower back and into your sides”
Intra-abdominal pressure refers to the pressure created inside your thorax when the diaphragm descends during a deep breath. If you’re unable to breathe deep enough to create pressure 360 degrees around your torso (primarily in the lower back and sides of the waist), the spine is more likely to move unfavourably under enough load and/or fatigue. Sometimes the diaphragm can become “stuck” for reasons including suboptimal static posture from sitting all day in a slumped-over position. If you’ve been breathing very shallow all day long and not allowing the diaphragm to descend naturally, it’ll take some time doing breathing drills and potentially some posture restoration drills to revive your ability to create intra-abdominal pressure. Sometimes, all you need is the physical cue of grabbing around your torso with 2 hands and trying to breathe deeply, filling up both hands with pressure as you inhale.
The muscles of the core are very important and should be “used” to some degree at all times, especially while lifting weights. However, being able to feel what using the core actually feels like is very difficult at first without the right understanding of what the core muscles are responsible for and the purpose behind using them. All the cues described above in this article can be applied to every exercise in the gym and will help ensure you’re getting the most out of every set.