Once upon a time, in a gym far, far away, exercisers would scrunch and crunch their abs in hopes of six-pack perfection. And since a buff belly is a sought-after feature, we engaged in this one-dimensional, dated workout.

It wasn’t until recently that fitness shifted its focus from the abs to the massive muscle groups surrounding them. To tone the tummy, and improve your overall health and physique, you need to train your core.

So what’s all the commotion about core strength? If you’re unaware of what your core muscles are, or where they’re located, you’re not alone. It’s common to confuse the core and abs as one and the same.

Here’s a simple 101 on your core, and why you should care about it:

Location: the neck, torso, hips and pelvic floor.

Muscles: the transversus abdominis, gluteus maximus, multifidus, rectus abdominis, internal and external obliques, erector spinae, lumbar muscles, the diaphragm, rotator muscles in the shoulder, cervical muscles around the neck, trapezius and latissimus dorsi. These layers of tissue form your body’s core.

Function: enables daily movements like walking, sitting and standing, as well as spinal stability, postural support, balance and structural alignment. The core muscles are also responsible for the pushing phase of childbirth and continence. It’s important for women of childbearing age to practice powering up their pelvic floor to help with labor and post-delivery recovery.

The core muscles sit on the skeleton like a corset. The tighter and stronger the strings (muscles) are tied, the more secure the body will be.

How to engage the core: take a deep breath, relaxing the shoulders and opening the chest. Brace the muscles of the belly as if you were about to take a punch to the gut. Sightly shift the pelvis to tuck the tailbone beneath the body. The lower abs and glutes should feel sturdy and engaged.

How to work the core:

Dead Bug

Begin on your back with your knees bent and feet planted on the ground. Push the lower back against the floor.
Elevate the arms and legs directly over the body, keeping the knees bent at a 90 degree angle.
Use your core strength to slowly lower the right arm with the left leg. Hold for two counts then return the arm and leg to the starting stance. Now practice on the left arm and right leg. Continue this alternating sequence for 60 seconds.

Plank Weight Shift

Start in a hand dominant plank position with a free weight placed on the outer right side of the body. Keep the spine straight and shoulders stacked above the hands. For those suffering from sore wrists, practice this on the forearms.
Using your left arm, reach under the torso for the weight. Grab it, then cross it under the body. Rest it on the outer left of your trunk. Try to avoid rocking at the hips when moving.
Now grasp the weight with your right hand. Steadily shift it to the right side of the body. Continue this sequence for 20 repetitions.out parallel to the floor.

Glute Bridge March

From a supine position, bend the legs so the feet are firm on the floor. Rest the arms at the sides of your body, palms down.
Push through your heels, lifting the hips until they form a straight line from the shoulders through the knees.
Once secure, push through your left heel, bracing the body and elevating the right leg. Hold for two counts, lower the right leg, then practice with the left leg. Keep your hips hiked throughout the entire exercise. Repeat this march for 20 counts.

For a strong, svelte body, always keep up with your core.

This article originally appeared on philly.com

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