Updated: Jun 22, 2021
Recommending a strong core is cliché. However, I think core stability is something we have a general idea of without refined knowledge of how the core works (Muscle Refinement for further discussion). It's like knowing that our cars need a well serviced engine to run properly; however, most of us couldn’t tinker with it to improve it. Additionally, we can’t hire someone to adjust our core to make us run more efficiently (although personal trainers can guide us. If we aren’t attuned to our core, that guidance is less effective).
Primary and Secondary Run Muscles
I want to talk about the muscles we use to run. To be clear, I don’t have a degree in anatomy, so this is my understanding from my years of grilling my physios, medical friends and teammates. I like to group run muscles into two categories, this is not a common grouping, but it is something that I refer to in my blog series:
Primary Muscles - They give you the power and force to go forward (ie. Quads, calves)
Secondary Muscles - They provide the stability so that the primary muscles push forward efficiently. Said another way, they hold your midsection tight, so that you don’t wobble around. This may be hard to believe, but running like a baby giraffe is not efficient. Crazy, right?
Why Core Matters
Let’s think about this in an analogue. Take either a car piston or a door hinge (keep in mind analogues are not perfect, this one is meant to highlight the importance of an engaged core).
If a piston or a hinge is too loose, power is lost or the hinge works inefficiently. When you engage your core, it holds your form so you don't lose power or work inefficiently.
If a piston or a hinge is too tight, the friction can cause loss of power and efficiency or slow the movement down. When you engage your core too much, you become rigid and loose efficiency.
This analogue is to help you understand the balance you want when engaging your core during a run. But don’t take my word for it, go for a run and try it out. See how it feels when you don’t engage your core at all or when you over engage it.
To help you visualize the degree of engagement you want, I like to think about it like holding a grapefruit in the palm of your hand. If you squeeze too hard, it's going to squish, while if you don’t squeeze enough it’ll fall out of your grasp. You want your core muscles to hug your midsection. Play around with finding this balance on an easy run, see what it feels like to hug too hard or loose. If you’re not a hugger, maybe think of a handshake and finding the right balance between firm and loose.
What Makes Up the Core
Now that you have an idea of the balance needed in your core and how to find it. We need to understand what makes up the core. I like to divide the core into four main parts to start playing around with. As you become more attune to your body, you may discover more nuanced areas or another area that needs your attention. This is the process of Muscle Refinement (Blog Link or Video Link).
Thinking about grasping that grapefruit, imagine it is resting on your palm and you only grasp it with your thumb and pointer finger. If you start to walk and speed up or the terrain changes, it’ll be harder to hold onto that grapefruit with just two fingers. If you use all your fingers and place them around the entire fruit, it'll be easier to stabilize it and move at higher speeds and rougher terrain. So you can't just engage your abs.
Lower Abs - Your lower abs are what most people think of when we talk about core. They are important but not the only part. When I visualize engaging my lower abs, I like to think of my rib cage and 2 inches below my belly button as a mouth. When I engage the lower core I think of closing that mouth by bringing the lower core and ribs together. Notice that as you engage your pelvis will also rotate up. I’ve often heard the pelvis described as a cup full of water and we need ensure that this cup doesn’t spill. We can use this movement to find the balance so that water is stable. Play around with this engagement and see what feels right to you.
On top of this, I also like to imagine pulling my belly button back to my spine. Find the balance that feels good and stable for your body.
Lower Back - I have a lazy lower back, it likes to let my abs do all the stabilizing. But you can’t have a stable mid-section by just engaging abs. You need to be secure all the way around. When I think of engaging my lower back I imagine squeezing my love handles so as to make them touch behind me. Keep in mind, they will barely move, but what this does is engages those muscles so that it gives your midsection the tension it needs to stay stable. Otherwise we flop around as we run.
Back Engagement Video - A quick 3 min video to help you visualize this engagement.
Gluts - Now that you’re squeezing your lower back, you want to continue that squeeze down towards your glutes. Again this will add tension to keep your core taught so that it doesn’t wobble as you run. Play around with engaging this and see what feels good.
Inner Thighs - Tension in your inner thighs brings a lot of stability. I like to think about this as if I’m pulling my inner thighs up into my perineum or base of my midsection. As you learn to actively engage this muscle it may feel weak and hard to engage. As it strengthens, you’ll start to be able to recruit the entire inner thigh all the way down to your knees, which provides a lot of stability. This may take some time and may come more naturally familiar with kegel exercises. If you haven’t, I think learning to engage this muscle will benefit you in the long run in other areas of your life. I’ll let you google the exercises if I’ve piqued your curiosity.
Remember from the blog on Getting Perfect Form, everyone starts at a different place. From other activities we have learned to engage some or all of our core. To start, we need to figure out what parts of the core are engaging and what's not. Then you can find your core balance for running. Remember that different factors impact your run and therefore your core balance. So as you run up hills, as your body fatigues, it's going to change the demand and pressure on your core. The more you practice this awareness, the easier and faster it is going to be to find the right balance and keep coming back to it.
The core provides the stability so you can run efficiently
I divide up the core into lower abs, lower back, glutes and inner thighs
Practice engaging and balancing the tension in these aspects of your core to give you the optimum stability for your body.
As you become in touch with your body and aware of ways to improve your running form, you have to be able to adjust your form as you're jogging. I like to think of this as Playing with your form as it changes along our journey to perfect run form.