The Science Behind the Most Effective Ab Workouts

The best ab workouts focus on strengthening your entire core, not just your "six-pack muscles."
Image Credit: spyderskidoo/E+/GettyImages

Carving an enviable six-pack isn't an easy feat — which is too bad, since it seems nearly everyone wants a defined set of abs. But too many people view a sculpted midsection as a kind of status symbol, reserved for the genetic elite or those who spend more time doing ab workouts than anything else. And that's simply not the case.

Yes, your genetics and diet influence how much muscle definition and how little body fat you have around your midsection. But the good news is that everyone has abs — regardless of how well you can see them. And that means that everyone can build better abs.


You might have to relearn a few things (nothing worth having ever came easily, right?), but by incorporating the principles below and trying some new exercises, you can create the ultimate ab workout.


What Makes the Best Ab Workout?

Ever wonder why sit-ups became such a popular exercise? Often, anatomy books state that the purpose of your abdominal muscles is to flex your spine. As a result, many think that by creating a "crunch" type movement, you'll build your abs the way nature intended.

Unfortunately, most anatomy books are at least 35 years out of date, says Mark Comerford, a researcher, physical therapist and founding director of Kinetic Control, a consulting agency that assists physiotherapists. While your abs do flex your spine, that's only one part of their job. Your abdominal muscles also help…

  • Create movement: If you're standing upright and bend forward at your waist as fast as you can — like a boxer ducking a punch — you'll feel your abs activate; since you're moving faster than the speed of gravity.

  • Counterbalance movement: If you were to start leaning backward from standing, you'll again feel your abs activate, but this time in a different way. Your abs are doing the opposite of what anatomy books tell you. Rather than flexing your spine, those muscles are fighting the extension of your spine to keep you from falling over.

  • Resist movement: Imagine you're standing upright with your arms reaching straight out at shoulder height, hands locked together. If a friend were to push your arms to one side, how would you resist their efforts? Your abs.


In order to build an effective ab workout, it's crucial to challenge your entire core in all of these different forms and motions. That's because almost every movement you do — both during your workouts and in your daily life — engages your core in some capacity.

Press a weight overhead, your abs engage. Stand on one leg, your abs are working. Struggle during a tough exercise and "cheat" a little on your form — yep, you'll probably feel your abs coming to the rescue.

What Are the Most Effective Ab Exercises?

It's the ultimate question for fitness fanatics: What's the best ab exercise? In 2001, the American Council on Exercise (ACE) sponsored research to find the answer once and for all. In their ranking of 13 of the most common ab exercises, bicycle crunches took the top spot based on activation of the rectus abdominis (those six-pack muscles). An outlier — the captain's chair — took second place.

Move 1: Bicycle Crunches



  1. Lie on your back with your hands behind your head, elbows out.
  2. Raise your head, neck and shoulders off the floor by engaging your abs.
  3. Twist to your left side, bending your right knee in toward your chest as you bring your left elbow to meet it.
  4. Return to center and repeat with the opposite arm and leg.

Move 2: Hanging Knee Raises on the Captain's Chair

  1. Climb up into the chair with your back pressed against the backrest, arms and elbows on the armrests (to support your body weight), hands gripping the handles and legs extended straight down.
  2. From there, pull your knees up toward your chest, engaging your abdominal muscles in the process.
  3. To finish the move, extend your legs back to the starting position and repeat.

Are Ab Workouts Effective?

That depends on what you're doing. While endless crunches might not be the best approach (see below for more on that), if you're strategic about the ab exercises you choose, you can create an incredibly effective ab workout.


One way to do that is with a stability ball. Incorporating this tool into your workouts has benefits for your entire core by targeting the entire functionality of the trunk, including flexion, extension, side-bending and rotation, according to ACE.

Try this four-move workout the next time you need an ab workout at the gym.

Move 1: Swiss-Ball Pike Rollout

  1. Start in a push-up position with your hands under your shoulders and shoulder-width apart on the floor, shins resting on top of a Swiss ball.
  2. Tighten your core muscles and pull your legs in toward your arms, lifting your hips in the air.
  3. Pause at the top of the rep and hold for one to two seconds.
  4. Lower yourself back down, sliding your legs back over the ball until your arms are under your shoulders.
  5. Remember to keep your abs braced and your back straight throughout the movement.

Reps: two to four sets of 6 to 12 reps


Move 2: Stability Ball Crunch

Performing crunches on a Swiss Ball or BOSU Trainer can help improve your balance and stability. And since you're on a round surface, you have a greater range of motion, which increases the challenge. (Bonus: This exercise ranked third for ab muscle activation in the 2011 ACE study.)

  1. Lie face-up with your lower back supported on top of the stability ball, feet flat on the floor and knees bent to 90 degrees.
  2. Raise your head and shoulders and "crunch" your rib cage toward your pelvis.
  3. Hold, then return to the start.


Reps: two to four sets of 6 to 12 reps

Move 3: Stability Ball Plank

  1. Place your elbows on the stability ball, hands clasped with feet hip-distance apart.
  2. Keep your body in a straight line from head to toes.

Reps: two to four sets of 30 seconds

Move 4: Stability Ball Push-Up

  1. Come to a high plank with your hands on the ball beneath your shoulders.
  2. Exhale, bend your elbows and lower your chest until it touches the ball, then push back up into a plank.

Reps: two to four sets of 10 to 12 reps

How Many Times a Week Should You Do an Ab Workout?

Unlike other muscle groups that need 48 hours to recover in between workouts, you can do ab work every day if you want. Watch your intensity, though. If your version of an ab workout includes deadlifts and medicine ball tosses, you'll want more time to recover in between sessions. However, body-weight core exercises like planks, dead bugs and bird dogs are generally OK to do every day.

Read more: A 10-Minute Pilates Ab Workout You Can Do Every Single Day

So Are Crunches Good or Bad for Abs?

In recent years, crunches and sit-ups have gotten a bit of bad press, as fitness experts and rehab professionals began speaking out against the exercise. Stuart McGill, PhD, a spine researcher at the University of Waterloo, found indications that performing too many crunches (or doing them too frequently) could cause a person's spinal discs to push out too far, causing pain and potentially a herniated disc.

Claims like this regarding the impact of crunches are highly debated. Carl DeRosa, PhD, founder of DeRosa Physical Therapy, says that your body position isn't responsible for putting pressure on your discs — it's how tightly you squeeze (or compress) your muscles.

Other experts, like spinal researcher Michael Adams, PhD, says that a person's discs can actually strengthen (like your muscles) and potentially become more resilient to injury as a result of doing abs exercises like crunches properly.

The bottom line: If you have a disc-related injury, crunches might not be the best exercise for you. But for healthy athletes, a few sets (not hundreds of reps) of well-performed crunches can help activate your abs. Just don't rely on them as your sole form of ab exercise.

And don't do them thinking they'll reduce belly fat, a landmark study from August 1984 and published in Research Quarterly for Exercise and Sport found sit-ups were ineffective at helping fight the battle of the bulge.

Read more: 3 Ab Exercises That Aren't Worth Your Time


How Do You Get a Six-Pack Fast?

So can you just do a bunch of bicycle crunches, hanging leg raises and Swiss ball crunches and wake up one morning with six-pack abs? Not so fast. Ab exercises alone won't banish belly fat to reveal the amazing abs underneath, according to a September 2011 study published in the Journal of Strength and Conditioning Research.

Chiseling your midsection requires a concerted effort that involves overhauling both your workouts and your nutrition (and often, a little help from your genetics). First, you'll need to clean up your diet and cut calories to reduce your overall body fat percentage so that you can show off those abs. That means cutting down on highly processed foods and alcohol and loading up on lean protein, fresh vegetables, complex carbohydrates and healthy fats.

Next, you'll need to make sure you're doing cardio. The higher the intensity, the more calories you'll burn. You can either opt for longer, steady-state bouts (like going for a long run) or shorter sessions of high-intensity interval training (HIIT). And lastly, yes, you'll need ab-specific exercises. Try one of the workouts below:

What Exercise Burns the Most Belly Fat?

Getting rid of belly fat (like sculpting six-pack abs) requires more than exercise. First off, you can't spot reduce belly fat. Rather, you'll lose belly fat all over with a combination of reducing your caloric intake, doing cardio exercise and adding strength-training sessions.

To maximize your time spent working out and fat-burning efforts, make HIIT a regular part of your workouts, according to a February 2018 meta-analysis published in Sports Medicine. That means, during your cardio workouts, for example, alternating between sprints and recovery.

Read more: How to Lose Belly Fat With These 7 Cardio Workouts