When a trainer says, "engage your core," your mind might be going in a million different directions: Should you squeeze your midsection? Tighten your abs? Hold in your gut?
The truth is, when you're engaging your core, you're doing a lot more than just contracting your abdominal muscles. Engaging your core takes practice, especially if you've never intentionally done it before.
Here, we break down how to contract your abs during exercise.
What Does It Mean to Engage Your Core?
Your core is one of the most complex muscle groups in your body that is comprised of your rectus abdominis (superficial six-pack muscles), transverse abdominis (deep, corsetting muscles), obliques (side abdominal muscles), pelvic floor and multifidi (deep back muscles).
So, when you're engaging your core, you're actively firing up these muscles, which surround your trunk and aid in the stability of your spine and pelvis, says Jen Fraboni, PT, DPT, physical therapist and creator of Jen.Health, an exercise and mobility program.
Engaging your core isn't as simple as learning how to tighten your abs during a workout. Core bracing actually involves using your breath to produce intra-abdominal pressure, which creates spinal stiffness to protect your back and activates your pelvic floor to stabilize your pelvis.
"[Core bracing] helps to aid in stability of the spine so we're not putting extra stress on the spine. It's not bad to bend the back, but when we put a little bit more load on the back, we want aid in that stability and make the body feel safe," Fraboni tells LIVESTRONG.com.
How to Engage Your Core
The level of core contraction you do during exercise depends on the demand of the movement or the load of the weight you're lifting, Fraboni says.
For example, you might feel more core contraction when you're lifting weights, like doing a back squat, versus doing an activity like yoga, where you're not going to need as much core bracing.
"Yoga requires much less of a brace in order to be able to improve mobility through the entire spinal segments," she says.
That said, whether you're doing deadlifts or holding a plank, bracing your core involves using your breath to guide you through lengthening and contracting your muscles.
To get into a rhythm of core contraction, Fraboni recommends practicing while lying on your back first. As you inhale, you want to expand the sides of your lower ribcage. As you exhale, think about lifting your pelvic floor up and in like an elevator. You should feel a mild-to-moderate contraction in your core.
"Rather than tightening and squeezing, you're lifting up and in. You're not thinking about max contraction as much as possible. You're thinking about a mild hold. You want to be able to notice a difference from relaxed to when you're mildly contracted and being able to sustain that through a lift, a squat or push-up," she says.
After your initial brace, you want to maintain that mild-to-moderate tension during your next inhale and feel a deeper contraction on your exhale. Your inhale will be smaller, but still around your lower ribcage, Fraboni notes.
As you inhale, focus on expanding the sides of your ribcage instead of your belly. Because your diaphragm (the muscle that helps you breathe) rests under your ribcage, the intention of your breath should be around your lower ribcage, Fraboni says.
Supine Core Contraction
- Wrap your hands around the sides of your ribcage and take a deep breath in. Feel your breath fill the sides of your lower ribcage, pressing into the sides of your hands instead of up into your neck.
- As you slowly exhale, think about lifting your pelvic floor muscles up and in, like an elevator, and stiffening your lower abdominals as they gently lower together with the exhale. This is where you'll feel a mild core contraction. Avoid forcefully blowing air out. You shouldn't feel any movement in your chest or pelvis.
- As you take your next inhale, relax your core muscles, including your pelvic floor. Maintain a mild-to-moderate contraction in your pelvic floor and abdominals as you inhale, and exhale if you're doing this in preparation for an exercise on your back.
When you're doing core or abs exercises lying down, such as crunches or a hollow hold, a common core-bracing cue is to press your low back into the floor. But Fraboni says what this actually does is put all of the pressure on your rectus abdominis, the six-pack muscle, which creates a coning effect.
A sign you're doing this is if you see a teepee form in your abdominal area that's hard and tight. This means you're not properly dispersing the pressure throughout your entire core and potentially puts more stress on your linea alba (a band of connective tissue that runs down the front of your abs).
While this won't necessarily cause diastasis recti (abdominal separation) or make it worse, Fraboni says balancing pressures in your body ultimately leads to a more balanced body.
Why You Should Engage Your Core
In terms of performance, bracing ultimately makes the core-focused exercises more effective because you're engaging all the muscles that surround your trunk. It also helps prevent injury because it creates spinal stiffness and stabilizes your pelvis.
"Learning to properly brace your core for various demands helps to control intra-abdominal pressure, which can help prevent excess pressure on your pelvic floor, linea alba and low back," Fraboni says.
Core bracing also allows you to hinge your hips and your upper trunk to rotate as needed to power activities, such as running, walking, lifting and moving from sit to stand, Fraboni says. By keeping your trunk and pelvis stable, engaging your core is what ultimately lets your shoulders, hips and legs drive movement.
"When we engage our full core from the pelvic floor to the abdominals and around the back, we help to prevent excess movement from the spine and pelvis and allow the majority of our movements to be driven from our power source — our glutes," Fraboni says.
You can also use your breath and brace to assist in rotational movements, so the power shifts from your feet, hips, spine and shoulders easier, according to Fraboni.
"Our abs have a rotational aspect, and when used in conjunction with the breath, it can help to utilize the full abdominal brace from the pelvic floor and through the trunk. As long as you are consciously breathing through exercise, you are utilizing an aspect of core bracing," she says.
Additionally, in daily life, having good midline control helps reduce increased sway that can lead to falls, Fraboni says.
When and How to Tighten Your Abs During a Workout
1. Core Bracing With a Deadlift
As you become more familiar with core bracing, you can start incorporating it into your strength-training routine, such as when deadlifting.
You want to inhale on the way down and exhale on the way up to aid in contracting your pelvic floor and core. Again, you want this to be a mild-to-moderate contraction because you want to be able to sustain it throughout your lift.
"As I breathe in during the hip hinge, I elongate my glutes, open up my pelvic floor and open up through my rib cage. And as I exhale to stand, I'm squeezing my glutes, pelvic floor and core," Fraboni says.
- Stand tall with your feet hip-width apart. Hold a dumbbell in each hand in front of your thighs, palms facing your body.
- Slowly inhale as you hinge at your hips and soften your knees to lower the weights toward the middle of your shins, maintaining a flat back.
- Make sure your spine is long and your shoulders are down and back.
- Drive your feet into the ground and slowly exhale, lifting your pelvic floor up and in, while squeezing your core and glutes to stand up as tall as possible.
2. Core Bracing With a Quadruped Plank
Before you get into a quadruped plank, complete a few breaths to practice core bracing: Expand the sides of your lower rib cage as you breathe in and exhale to lift your pelvic floor up and in, dropping your ribs toward your pelvis. You should feel a mild contraction that you'll sustain throughout the exercise.
- Get into a tabletop position with your shoulders stacked directly over your wrists and your hips over your knees.
- Protract your shoulders by pressing your hands into the ground and your sternum away from the floor (or your chest away from the floor without rounding your upper back).
- Take a breath in, filling the sides of your ribcage. Then, slowly exhale as you lift your pelvic floor muscles up and in and contract your core, dropping your ribcage down toward your pelvis without moving your spine.
- Inhale, and on the next exhale, lift your knees an inch or two off the ground and hold. Continue to do pelvic and core bracing as you breathe.
3. Core Bracing With a Forearm Plank
When holding a plank, you want to follow the same core-bracing cues of expanding the sides of your lower rib cage and then exhaling to lift your pelvic floor up and in, allowing your ribs to drop down together toward your pelvis. With each exhale, think about contracting your core tighter.
- Lie down on your stomach with your forearms flat on the ground. Your shoulders should be directly over your elbows, with your hands and wrists in line with your elbows.
- Begin by pressing your elbows down into the ground and lifting your chest away from the floor. As your body continues to lift off the ground, draw your ribcage toward your pelvis and tuck your tailbone under as you come up to a plank on your knees.
- Tuck your toes under to press into a full forearm plank.
- Hold this position as you inhale to fill the sides of your ribcage with air and exhale to lift your pelvic floor up and in as your ribcage drops toward your pelvis. With each exhale, think about contracting your core tighter.
4. Core Bracing With a Shoulder Press
Regardless of if you're doing a shoulder press kneeling or standing, focus on using your breath with a full abdominal brace to drive the weight overhead.
- Come to a kneeling position and hold a dumbbell in each hand by your shoulders, elbows at a wide diagonal and palms facing slightly in. (You can also do this move standing.)
- Take a breath in, filling your low ribcage with air. Keeping your spine tall and your chest proud, while maintaining a slight tuck under your pelvis, press the weights overhead, finishing with your biceps by your ears. As you press the weights, slowly exhale, allowing your pelvic floor to lift up and in and contract your core.
- Slowly lower the weights back down to the starting position as you inhale.
5. Core Bracing During Cardio
You don't have to think about consciously keeping your abs activated and engaged when doing cardio exercises, such as walking and running. As long as you're breathing through the sides of your ribcage and not up from your chest, you're naturally engaging your core, Fraboni says.
"We want to expand from the sides of our ribcage as we're walking. This helps to disperse the pressures laterally to the sides and back of our core. When we exhale, we contract just by focusing on our breath. You'll naturally increase that contraction when you're going for a sprint or run," she says.
Should You Engage Your Core While Sitting or Standing?
As with cardio exercise, Fraboni says that you don't have to think about contracting your core when sitting or standing. The level of core bracing depends on the demand of the movement or task, so if you're just sitting or standing, the demand is pretty low.
"I think our society tends to overprioritize this idea of perfect posture, but when we do this and we're trying to contract everything throughout the day, all we're doing is turning on our muscles more than they need to be," Fraboni says. "So, if you're not really doing anything, you should be more relaxed. It's increased tension over time that leads to feeling more pain, tightness and stiffness."
When you're standing, you want to naturally stack your body with your head over your hips and breathe from your ribcage without contracting. It's the same with sitting, whether you're supported on your back or on your sit bones.
"We rely on the natural alignment of our head over our hips to hold our body in place and allow our skeleton to do its job and not muscle force to do the work," she says.