The best core workouts don’t only hit your rectus abdominis, or what you think of as your “abs”—they fire up the entire area. And this dumbbell abs workout does just that, which is super important if your goal is to build well-balanced, functional strength.

A strong core is crucial for a whole bunch of reasons. And nope, we don’t just mean because it can help you crush a set of sit-ups of push-ups, or hold a side plank without sagging. Core strength is actually way more functional than that, personal trainer Sivan Fagan, CPT, owner of Strong with Sivan, tells SELF: It helps you maintain stability throughout your entire body, which helps reduce your risk of injury in a ton of different scenarios—from squatting to pick up a laundry basket to pulling a heavy box off a high shelf to deadlifting a stacked barbell at the gym.

One reason for the body-wide benefits? Your “core” actually is more comprehensive than you may think. Sure, it includes your “abs”—the muscles that run vertically along your abdomen—but it also involves your diaphragm, transverse abdominis (deep-set muscles that wrap around your entire torso), pelvic floor muscles, internal and external obliques (which run along the the sides of your midsection), and spinal muscles (which range from your low back all the way up to your neck and help keep you stable), Fagan says.

Together, these muscles create something you can think of like a cylinder, she says. That’s why it’s important to strengthen all parts of it, rather than honing in on only one area. For your core to really nail its job of stabilizing your spine and pelvis, it needs all the different muscles to contract and fire together. Your core is only as strong as all the sum of all its parts, which is why it pays to target every area in this mighty muscle group.

You can actually build strength in your core in two ways: through movement and anti-movement. The former involves dynamic exercises, like side bends or crunches (which work through flexion or bending) or twists (which work through rotation). That latter has to do more with resisting movement, which requires your core to really fire to keep you steady (like when you’re pressing, rowing, or planking). Folks tend to think of the dynamic moves as “abs exercises” and may forget about the anti-movement ones—but both are important. In fact, exercises where you resist motion are actually the foundation of good core strength, says Fagan.