Want Six-Pack Abs? Here's How To Build a Solid Core

Many weightlifters skip dedicated ab work, assuming compound lifts — like squats and deadlifts — provide enough core engagement. And while they do activate the trunk musculature (Schoenfeld, 2010), they’re not enough if you want visibly defined abs or improved core control. That’s where structured core training comes in.

Bodybuilders chasing defined abdominal “peaks” don’t rely on squats alone. And neither should you.

Want defined abdominal muscles? Train them the same way you'd train any other muscle group for hypertrophy...

My approach is straightforward: train your abs like you train your other muscle groups — 2–3 times per week, with focused intensity and progressive overload, using weighted movements to bring yourself to (or close to) failure. I train abs heavy twice per week and do bodyweight-focused training (including isometric exercises) for my third weekly session to allow for recovery. Keep reading for a heavy hypertrophy-focused routine. For those lighter days I mentioned, check out any of these 10–20-minute videos by Maddie Lymburner.

The Core: More Than Just Your Six-Pack

Your core is a complex system of deep stabilizers and large movers:

• Local stabilizers: Deep muscles like the transverse abdominis and multifidus that stabilize your spine.

• Global movers: Larger muscles like the rectus abdominis and obliques responsible for movement and load transfer (Bergmark, 1989; McGill, 2010).

This article focuses on hypertrophy training for the rectus abdominis and obliques — the muscles most responsible for core aesthetics and function. That's part of why I like to include a lighter day each week that hits my global movers — and I also make sure to work in exercises that strengthen the lower back (like deadlift variations, hip thrusts and back extensions/reverse hyperextensions) on full- and lower-body days.

Isometric vs. Isotonic Core Training

• Isometric exercises involve muscle contraction without movement—great for stability and posture (e.g., planks). You can do these exercises as often as you'd like since they generally produce little muscle damage and cause less delayed-onset muscle soreness (DOMS) (Allen et al., 2018; Hody et al., 2019)

• Isotonic exercises involve movement and tension through a range of motion—crucial for hypertrophy and strength.

A smart ab routine includes both.

👉 Russian twists, for example, involve both: your core holds isometrically while you rotate through an isotonic range.

Ab Training Structure: My Weekly Blueprint

Each workout hits:

• Upper rectus abdominis

• Lower rectus abdominis

• Obliques

Each region gets:

• One isotonic exercise (two options provided below, do only one per workout)

• One isometric finisher

Sample Heavy Core Routine: Strength and Hypertrophy

1A. Hanging Leg Raise With Posterior Pelvic Tilt

3 sets x 15–20 reps (or add load via ankle weights and reduce reps accordingly)

▶ Watch demo and explanation

🔹 Tip: Use hanging straps if your grip fatigues before your abs do.

🔹 Why PPT matters: To train the lower abs, you must rotate your pelvis into a posterior pelvic tilt. Standard leg raises target the hip flexors more than the abs. Posterior pelvic tilt directly activates the lower rectus abdominis (Escamilla et al., 2006).

1B. (Alternate Option) Supine Leg Raise With Posterior Pelvic Tilt

3 sets x 8–15 reps

▶ Same video as #1A

🔹 Emphasize curling your hips off the bench (or floor) at the top of the rep.

2A. Cable Crunches

3 sets x 8–12 reps

▶ Watch demo

🔹 Keep hips stable, focus on spinal flexion, and use a full range of motion.

2B. (Alternate Option) Weighted Ball Crunch

3 sets x 15–20 reps

▶ Watch demo

🔹 Use a plate, dumbbell or medicine ball. Pause and squeeze at peak contraction.

3A. Cable Twists (Obliques)

3 sets x 8–12 reps per side

▶ Watch demo

🔹 Resist using your arms — let your obliques do the work.

3B. (Alternate Option) Plank Dumbbell Drag (Feet Elevated)

3 sets x 16–24 reps (alternating sides)

▶ Watch demo

🔹 Keep hips level. Don’t twist—resist rotation to engage obliques and stabilizers.

4. Plank Hold (Isometric)

1–3 minutes

▶ Watch demo

🔹 These will get easy quickly. I make mine harder by wearing a weighted vest and cycling through a few movements like these during the hold.

5. Side Plank Hold  (Isometric)

1–2 minutes (30–60s each side)

▶ Watch demo

🔹 These will get easy quickly. I make mine harder by wearing a weighted vest and adding rotational movement (or hip dips or leg lifts, etc.). Here are some ways you can progress them.

6. Hollow Body Hold  (Isometric)

1–2 minutes

▶ Watch demo

🔹 Progress these by assuming a more challenging position, adding rolling movement, and by holding a dumbbell or weight plate.

Train for Growth: Use Progressive Overload

Want visible abs? You need to grow the muscle and lower your body fat. Abs respond to progressive overload like any other muscle group.

I like to use the double progression model:

1. Start at the low end of your rep range.

2. Increase reps week by week.

3. Once you reach the top of the rep range, increase weight and drop back down.

This simple system ensures continuous progress while managing fatigue.

What About Nutrition?

“Abs are made in the kitchen.” True — but incomplete. Abs are built in the gym and revealed through diet. No matter how hard you work your core, you're not going to see definition until you get below ~15% body fat for men or ~19% for women. You need to reduce body fat through caloric control and consistency.

👉 Read: Everything You Need To Know About Nutrition for Weight Loss

Bonus Moves for Aesthetic Gains: Serratus and Lower Chest

If you’re chasing a more defined and aesthetic torso, it’s worth paying special attention to a few often-overlooked muscles: the transverse abdominus, the serratus anterior and the lower chest.

For a tighter-looking waist and better core stability, add stomach vacuums to your routine. This isometric move targets the transversus abdominis — the deep “corset” muscle that wraps around your midsection — helping to cinch the waist and support your spine. Strengthening this muscle has been shown to improve spinal stability and may help reduce lower back pain (Critchley, 2002). To perform: exhale fully, then draw your belly button in toward your spine as if trying to make your waist as small as possible. Hold the contraction for 15–30 seconds while breathing normally, rest, and repeat for 3–5 sets. You can do them standing, kneeling, or lying down — just keep the squeeze strong and controlled. Practice a few minutes daily for the best results.

▶️ Watch bodybuilding champion Chris Bumstead demonstrate the stomach vacuum here.

The serratus anterior is a fan-shaped muscle that wraps around the ribcage, originating on the upper ribs and inserting along the inner edge of the shoulder blade. Functionally, it’s responsible for scapular protraction — pulling the shoulder blades forward — and stabilizing them during pushing movements. From an aesthetic standpoint, a developed serratus creates sharp, horizontal lines along the sides of your ribcage, helping to define the separation between the chest, lats, and abs. It’s a subtle but powerful feature that gives a lean torso a more “shredded” look.

▶️ To target the serratus anterior, try the Plank Plus and Push-Up Plus — demonstrated in this ATHLEAN-X video.

And a defined lower chest helps “cap off” the abs and creates a clean, sculpted line separating the torso from the upper body. It rounds out the pecs and enhances overall symmetry, especially when body fat is low.

▶️ Some of the best exercises for the lower chest — including Dip Plus, Straight Bar Dips, and Standing Cable Presses — are featured in this ATHLEAN-X article.

References

• Bergmark, A. (1989). Stability of the lumbar spine. Acta Orthopaedica Scandinavica Supplementum, 230, 1–54.

• McGill, S. M. (2010). Ultimate Back Fitness and Performance. Backfitpro Inc.

• Allen TJ, Jones T, Tsay A, Morgan DL, Proske U. Muscle damage produced by isometric contractions in human elbow flexors. J Appl Physiol (1985). 2018 Feb 1;124(2):388-399. doi: 10.1152/japplphysiol.00535.2017. Epub 2017 Oct 26. PMID: 29074710.

• Hody S, Croisier JL, Bury T, Rogister B, Leprince P. Eccentric Muscle Contractions: Risks and Benefits. Front Physiol. 2019 May 3;10:536. doi: 10.3389/fphys.2019.00536. PMID: 31130877; PMCID: PMC6510035.

• Schoenfeld, B. J. (2010). Squatting kinematics and their application to performance. Journal of Strength and Conditioning Research, 24(12), 3497–3506.

• Escamilla, R. F., et al. (2006). An EMG analysis of abdominal activity during trunk curls. Journal of Strength and Conditioning Research, 20(3), 471–478.

• Wakahara, T., et al. (2012). Nonuniform muscle hypertrophy: relation to muscle activation. Medicine & Science in Sports & Exercise, 44(11), 2158–2165.

• Critchley, D. J. (2002). Instructing pelvic floor contraction facilitates transversus abdominis contraction during low-abdominal hollowing. Physiotherapy, 88(9), 553–557. https://doi.org/10.1016/S0031-9406(05)60117-9