What's The Deal With Our Core?

Have you ever been to fitness class and the instructor cues every one to keep their core tight? Apart from the weird cue of keeping your abs flexed, what exactly does this mean? Trainers want you to maintain a tight core in order to protect your spine and avoid any spinal flexion and extension during the exercises as this leads to spinal disc injuries.
That is all great and dandy, but keeping your core tight/engage/flexed is a little more complex than just squeezing your abs.
First of all, your core is more than just your abs. Depending on trainers, it involves slightly different muscles. I always tell my clients that the core is the deeper muscles around your spine, shoulder blades and hips. In my opinion your glutes are also part of your core because they help stabilize the hips. To keep things simple, your core is what stabilizes your trunk and hips.
The thing with the deep muscles close to your spine is that you can’t just cue them to be tight. So here is what I do myself and what I get people to do.
Breath correctly and at the right time
Breath with your diaphragm, not your throat. This means deeper, slower breath. When you inhale you should feel your ribcage expanding forward but also sideways on each side. Get in the habit of inhaling during the eccentric part of the exercise and exhaling during concentric part.
For example, during a squat, breath in on the way down and exhale on the way up. Imagine your spine and lungs like a a stick (spine )resting on a big ballon (lungs). If the balloon has no air in it, the stick moves in on it. If the balloon has a lot of air in it, the stick will not move at all.
Maintain your lower ribs and pelvis parallel
When you stand up with good posture with a neutral spine, meaning no spinal flexion or extension, your lower ribs are parallel to your pelvis floor. Whenever you move your body be it with squat, deadlifts, lunges, jumps or whatever else, you want to maintain that alignment. This is where the classic core engagement comes in.
Everyone has a different spine so telling people to keep their back straight is a bad cue. Whenever you hear that, just think “Keep my rib to pelvis parallel alignment”. I know its a mouthful so instead just think “ribs to pelvis”.
Pull your shoulders blades down slightly
There are tons of muscles that attach to your shoulder blades. Keeping them locked in during any movement will help you be more stable during it.
Think about pulling your shoulder blades down and in very slightly. This should open your shoulders a little and push your chest forward a bit. Dot not compromise your rib to pelvis alignment by doing so.