Core: the central or most important part of something.

Or, the center of a mass or body. Anatomically, this term would refer to your torso, glutes and hips.

Extremity: the furthest point or limit of something.  

Or, the pieces furthest away from that center of mass or body. Anatomically, this term would refer to your arms, legs, hands and feet.   

So, knowing that, what do you think the phrase “core to extremity” means in relation to functional fitness?

We’re taking our energy and movement from the central (read: most important part!) part of our body and pushing it out to the extremities or outer limits of our body. This uses the larger muscle groups like the torso, glutes and hips as the powerhouse to then drive that power outwards to the smaller muscle groups in our arms and legs.

In other words, we are starting any movement in a workout by fully engaging those core muscles before progressing outward and then engaging those muscles further from the center of your body.

But why is this important?

Functional fitness, and CrossFit, are all about efficiency. When we practice lifting movements, we are trying to move a load as efficiently as possible. Initializing these movements from our core is far more effective and efficient because it allows us to use that core muscle group to it’s full potential.

As an example, let’s consider the thruster. Simply put, a thruster is a front squat into a push press. But what happens when we start pressing before the squat movement is complete?

Answer: You’ll be limited by the amount of strength in your arms.

Because you haven’t fully opened your hips, there’s still a bunch of power housed in there. The bar has already left its resting place on your body, so you won’t be able to translate that power now to the bar – it’s already in motion, and your arms are already doing the work, without the help of that power in your hips, glutes, and torso.

Take the above photos as an example of this. See how in the middle photo, he’s standing with his hips completely open, and the bar is still on his shoulders? This lets him drive that power from his hips up through his core, to his shoulders, and move it much more easily than if he had started pressing before he stood all the way up and reached full extension.

This principle doesn’t just apply to weightlifting movements; it applies to bodyweight movements also. Think about kipping – you have to generate that power from your core and your hips in order to efficiently work through that range of motion, whether it be a pull up, a handstand pushup, or something else. Or, consider a simple push up. If your midline isn’t tight in a push up, if your core is loose, you’re either going to have a sag in your low back or your butt up in the air. Keeping that core tight allows you to hold that plank body position and effectively transfer that power being generated from your midline through to your back, shoulders and arms to complete the push up.

When we don’t focus on the “core to extremity” principle in our workouts, we end up working harder than necessary to do the work asked of us. Tasks become more challenging when we’re not engaging our larger muscle groups at the start of a movement.

This engagement doesn’t just give us the best power output – it helps with speed, and protects us from injury. It improves balance and stability. Think of your core like the foundation of house – it’s what you’re built on. And if the foundation of your house isn’t strong enough to support the house itself, it’s going to collapse at some point.
So the next time you’re in the gym, focus on maintaining stability in those core muscle groups. Visualize the power and energy coming from the core, traveling through your body to your extremities, and into the bar to get it moving. Use that transfer of energy, and you might just find your workouts feel a little bit easier and a little bit more stable than they did before.