Here's something most beginner core routines get backwards: your core's most important job usually isn't to move your spine — it's to resist unwanted movement in it. Crunches train the first job. Planks train the second. Most people default almost entirely to the first and barely touch the second, even though the second is what actually protects your lower back in everyday life.
I used to think crunches were basically the whole story for core training. My abs got some work, sure, but my lower back stayed vulnerable during heavier lifts, and I couldn't figure out why until I learned that a strong core isn't just about how many crunches you can do — it's about how well your core can resist being pulled out of position.
A quick note before you start: if you have a lower back condition or recent abdominal surgery, check with a doctor or physical therapist about which core movements are appropriate for you.
The Move vs Resist Map
Core exercises fall into two functional categories, and most beginner routines only cover one of them.
| Core Function | What It Trains | Example Exercises |
|---|---|---|
| Move (flexion & rotation) | Abs and obliques contracting through a range of motion | Crunches, Russian twists |
| Resist (anti-extension & anti-rotation) | Core stabilizing against forces trying to move it | Plank, Bird Dog, side plank |
The core idea: "Move" exercises are what most people picture when they think of ab training — crunches, twisting movements. "Resist" exercises train your core's other, arguably more important job: keeping your spine stable while everything else around it moves, whether that's during a heavy lift, a sprint, or just carrying groceries up a flight of stairs.
Best Exercises by Function
Move (Flexion & Rotation)
Crunches — Lying on your back with knees bent, lifting your shoulders off the floor trains the upper abs through spinal flexion.
Russian Twists — Sitting with knees bent and leaning back slightly, rotating your torso side to side trains the obliques through active rotation.
Resist (Anti-Extension & Anti-Rotation)
Plank — Already covered in our guide 10 Best Full Body Workout Exercises for Beginners, the plank trains your core's ability to resist your hips sagging or your lower back arching — a genuinely functional skill.
Bird Dog — Also covered in that same guide, extending opposite arm and leg while on all fours challenges your core to resist rotation and keep your spine stable.
Side Plank — Holding your body in a straight line supported on one forearm trains resistance to lateral flexion, directly targeting the obliques' stabilizing role.
Building a Complete Core Routine
A well-rounded core session trains both functions, not just crunches. A simple beginner-friendly example:
| Exercise | Sets x Reps/Time |
|---|---|
| Crunches | 3 x 15-20 |
| Russian Twists | 3 x 15-20 (each side) |
| Plank | 3 x 20-30 seconds |
| Side Plank | 2-3 x 15-20 seconds (each side) |
This structure gives real attention to both moving the spine and resisting movement in it — a more complete approach than defaulting to crunches alone.
Common Mistakes With Core Training
Only doing "Move" exercises like crunches
This is the single most common gap in beginner core routines. Anti-extension and anti-rotation work often gets skipped entirely, despite being more directly tied to real-world back protection.
Rushing through reps to add volume
Fast, uncontrolled crunches or twists rely on momentum rather than genuine muscle effort. Slow, controlled reps produce better results than fast sloppy ones. For more on avoiding this kind of training shortcut, see our guide 10 Common Workout Mistakes Beginners Should Avoid (And How to Fix Them).
Holding your breath during planks
Bracing your core doesn't mean holding your breath entirely — steady breathing while maintaining tension actually trains the stabilizing function more effectively than breath-holding does.
A strong core also directly supports your squats and deadlifts — check our guide Best Leg Exercises to see how the two connect.
Frequently Asked Questions
Do I need to do crunches to get visible abs?
Visible abs come down more to overall body fat levels than to any specific ab exercise. Crunches and other core work build the muscle underneath, but diet plays the larger role in whether that muscle is visible.
Is a plank better than crunches for the core?
Neither is inherently better — they train different functions. Planks build stability and resistance to movement, while crunches build strength through spinal flexion. A complete routine includes both.
How often should beginners train core?
2-3 sessions per week works well for most beginners, and core is often trained more frequently than other muscle groups since it recovers relatively quickly.
Can I train obliques without twisting movements?
Yes. Side planks train the obliques through their stabilizing (anti-rotation) function without any active twisting, which can be a useful alternative if rotational movements feel uncomfortable.
Final Thoughts
Your core's real test isn't how many crunches you can knock out — it's how still your spine stays under a heavy squat or an awkward lift. Train for that test, not just for the mirror.
Building your training week from the ground up? Our guide 10 Best Full Body Workout Exercises for Beginners is a good foundation to layer this onto.
Does your current core routine lean toward "move" exercises or "resist" exercises? Let me know in the comments.