Every few years, another device comes out on the market that promises a six-pack. Remember the ab lounger? Should lounging and abs really be in the same sentence? Even more recently, a battery-operated ab belt that stimulates your abs while you sit or stand. Sadly, building flat, defined abs isn’t that easy. If it was, everyone would have a six-pack.
Another fallacy about ab building is that you can “crunch” your way to flat abs. Yes, crunches stimulate your ab muscles more than wearing an ab belt but they alone are unlikely to give you the sleek, firm abs you’re looking for. In fact, some fitness trainers believe that the only ab exercises you need are squats and deadlifts, two compound exercises that work multiple muscle groups, including your core. If you aren’t doing these exercises regularly, you should be. These two moves work the muscles in your lower body as well as the muscles in your back and abs. Because you’re working multiple muscle groups, the calorie burn is greater than when you do crunches as well. One reason it’s hard to get your abs to pop is there’s too much body fat covering them. Compound exercises, like squats and deadlifts, burn more fat than isolation abdominal exercises on a mat. When you do crunches, you feel it in your abs but you’re not burning many calories.
When you squat, you feel it more in your quads, hamstrings, and thighs than you do your abs, but your entire core is actually working to support and stabilize you as you squat down and come back up. Then there’s the deadlift, a compound exercise that simultaneously works your lower body, core, as well as your upper body. As with squats, most of the muscles in your body are coming into play as either movers or stabilizers.
One benefit of squats and deadlifts as opposed to focused ab exercises, like crunches, is deadlifts and squats work your abs AND back muscles. In contrast, crunches primarily work the rectus abdominis and obliques for oblique crunches, and do little to strengthen your back muscles. If you focus too much on working your abdominal muscles and ignore the muscles in your back, you can develop muscle imbalances that lead to injury or back pain. With moves like deadlifts and squats, you get balanced core training.
Are Squats and Deadlifts All You Need for Defined Abs?
Don’t give away your exercise mat and make squats and deadlifts your “go to” ab exercises just yet. One way you measure the degree of muscle activation with various strength-training exercises is an electromyogram or EMG. An electromyogram tells you how much a muscle or muscle is activated with various movements. One study that measured muscle activation using EMG found that the rectus abdominis (big muscle in the front of the abdomen) is only weakly activated with deadlifts and even less so with squats. In fact, based on EMG activity, push-ups activate the rectus abdominis more than deadlifts OR squats.
When researchers measured EMG activity for the external obliques, muscles at the sides of the abdomen, activation was better but still was less than oblique activation during push-ups. The portion of your core you’re working most when during squats and deadlifts is the posterior core. While it’s important to work your posterior core for balance, doing so won’t get you a six-pack.
Yes, You Still Need Isolation Ab Exercises
Yes, you should do squats and deadlifts but don’t count on them alone to give you six-pack abs. As EMG studies show, neither squats or deadlifts strongly activate the rectus abdominis and that’s the muscle you hypertrophy for ab definition. The strength of deadlifts and squats are that they activate the core muscles in a more balanced way than isolation ab exercises. However, to hypertrophy the rectus abdominis, you still need ab-focused exercises – but crunches alone aren’t enough. You’ll get better results by including isometric exercises like planks and plank variations.
A common mistake people make when doing ab exercises, like crunches, is training them differently than other muscle groups. If you’re trying to develop leg or arm muscles, you don’t grab a super-light pair of weights and do 30 or 40 reps. You add resistance and gradually increase that resistance over time to abide by the principle of progressive overload. If you’re trying to hypertrophy your abs, the same should be true. For one, slow down the movement to increase the time under tension. Once you can do 20 slow reps, it’s time to make the exercise harder. You can do this by changing your arm position, by extending your arms over your head, or by holding a dumbbell when you crunch.
To make matters worse, most people “cheat” when they crunch. It’s easy to tap into momentum and use your upper body to push yourself off the mat. Bad move! This takes the stress off your abs. Also, when you lift your body too high, you work your hip flexors more than your abs. When you crunch, lift your shoulders to a height of no more than 45 degrees. According to a study published by the American Council on Exercise, the traditional crunch, based on EMG, is one of the most effective ab exercises – but only when you use good form and avoid momentum.
Don’t forget to add crunch and plank variations to hit your abs from different angles. For growth and change, you need to vary the stress you place on your abdominal muscles.
The Bottom Line
Squats and deadlifts support ab development but they target your posterior core rather than the muscles in the front of your abs. That’s why you STILL need targeted abdominal exercises, like crunches and planks. However, deadlifts and squats burn more body fat than isolation exercises. One of the reasons people don’t have ab definition is because there’s a layer of fat covering the muscles. Deadlifts and squats will help you shed that fat faster than ab exercises you do on a mat. HIIT training helps as well.
The take-home message? When working your abs, don’t be too “crunch happy.” Make sure you’re doing SOME crunches along with other ab-focused exercises, like planks. Keep deadlifting and squatting though! These exercises are far too important for functional strength and muscle development to ignore.
T-Nation. “Core Confusion: The Truth About Squats & Deads”
J Strength Cond Res. 2013 Jun;27(6):1684-98.
ProgressiveFitness.net. “Why Squats and Deadlifts Are Bad Abs Exercises”
American Council on Exercise. “Abs! Abs! Abs!
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