How to Do a Reverse Crunch Properly

Abs are the crowning achievement for almost any body type.

Sure, big pecs are great if you’re looking for bulk—but what if you’re going for the lean, shredded vibe? Same goes for massive arms; we can all respect the work that goes into cultivating them, but not everyone wants to look like a muscle head. And not everyone wants to look go full ottermode either.

But then, there are the abs.

Whatever your fitness goal is, the abs will always be there, waiting for you at the end. Sure, a lower body fat percentage makes them easier to get and gives a more shredded look, but jacked-up dudes can have them as well. They’re the crème de la crème of a physically fit body.

Men love ‘em, women love ‘em, you love ‘em, we love ‘em. And if you’re ready to work for them, well do we have the exercise for you.

The reverse crunch is the exercise to do if you’re looking for that elusive 6-pack—read on to find out why and how you should do it.

Getting to the Core 

We’ve all wanted to lose a bit of belly fat at some point, which will only really happen if you expend more calories throughout a day than take in—but it is possible to develop the abdominals and expend calories at the same time. 

Working the muscles in the trunk area, collectively known as the core muscles, will improve posture while also helping your other lifts, and functional and athletic fitness in general. Not to mention minimizing your chance of injuring yourself (especially your back). 

The hype around the core began in the 90s when researchers found that people with healthy backs automatically engaged their cores before trying to move an arm or a leg. Ever since then, core strength has been at the forefront of training regimes—also extending all the way back to WWII with the creation of Pilates to rehabilitate soldiers. 

A well-developed core is the base for essentially all movements that we do, from reaching a shelf, to lifting a barbell, to throwing a ball. The benefits of a strong core extend much further than a head-turning 6-pack.

Strengthening the Core 

Almost all compound, full-body movements will engage the core in some way. From the Olympic lifts to the traditional barbell/deadlift/squat lifts, to the humble push-up and the pull-up. All of these, when performed properly while having the correct muscles activated, will help to develop your core. And of course, we all know our favorite abdominal exercise, the sit-up.

However, a lot of criticism has been launched at certain workouts that specifically hit the core, making the ab exercise waters a murky affair to wade into. Let’s take, for example, the classic crunch.

Essentially everyone is familiar with this simple bodyweight movement, only requiring you to lay on your back with your hands behind your head and lift the upper body off the floor. This is, as most of us know, an exercise that’s not usually wholeheartedly recommended by people. Most of those reasons are due to neck pain, but there are techniques to minimize that.

But crunches are especially hard on the back since they push your curved spine against the hard floor. Furthermore, they also activate the hip flexors—muscles running from thighs to the lower lumbar vertebrae. What this means, however, is that hip flexors which are too tight will usually pull on the lower spine, often leading to lower back pain. 

So, while a popular ab workout, crunches are definitely not the most effective way to tone your abdominals—at least if you’re aiming for longevity as well. Which is where the reverse crunch comes in.

Spicing Up the Crunch 

The reverse crunch is a more advanced, but better-for-your-back substitute for traditional crunches. Its greatest benefit is that it doesn’t require you to bend your spine back and forth repeatedly, which also maximizes the time your muscles are under tension (getting you greater gains in the long run).

The biggest mover in the reverse crunch is the rectus abdominis—aka, the six-pack. And while it might sometimes look like 6 or 8 separate muscles, it’s actually just a single large muscle spanning the front of your body. What reverse crunches specialize in, however, are the lower abs. It hits this area much more effectively and is a good way to go if you’re searching for those ever-elusive bottom abs.

The other major movers in this exercise are the obliques and the transverse abdominals. The obliques are in charge of stabilizing the spine, while the transverse abdominals stabilize the core. The latter muscle group, transverse abdominals, are the deepest part of the abdominal muscles and are especially important when it comes to reverse crunches.

Not only are you focusing on looking good, but you’ll also be engaging your body in a way that builds real strength and functionality, helping you avoid injuries.

Why the Reverse Crunch?

We’ve already touched on the fact that reverse crunches work your core more safely and more effectively than traditional crunches, but the benefits don’t stop there.

The fact that they’re a more difficult exercise overall makes them much more engaging with your muscles. While you might be able to pop out a bunch of crunches and go for extremely high reps, the reverse crunch will humble your crunch rep count—at least if you do them correctly.

This type of high-intensity workout for an extended duration is the key to building a strong and sexy core.

Who Should Do Them and How Often 

While working out the core is essential if you’re trying to alleviate (or get rid of) back pain, it’s generally advised to stay away from reverse crunches (and regular crunches) if you do have pain in that area.

And since the reverse crunch is a slightly more advanced maneuver, you’re better off building a solid base of strength in your core before including it into your workout plan. The same goes for if you’ve got a history of back pain—it’s better to start off slow and condition the core with more basic exercises.

However, if you’re looking for the promise of a 6-pack and don’t have back pain, this can be a terrific exercise to add to your weekly gym routine. Especially if you’re on your feet all day or sitting, this is a great way to fire up your core and help prevent future back injuries. 

However, even if you do want to incorporate reverse crunches into your routine, it’s important to keep them as a complementary exercise. 

Abs exercises such as side planks and rollouts (stability exercises) are still necessary to build the power and control in your core—especially when training for sports or for lifting. This movement is great to incorporate in an abs workout at the end of a gym session to really hit the abs hard before you hit the locker room.

How to Do Reverse Crunches

These require no equipment so you can do them just about anywhere you have some space. As always, form is paramount when performing exercises—but it’s especially important during moves that can potentially harm your back. 

However, you can opt to use a bench. This will affect your hand positioning and stability. If you choose the floor, your arms will be going downwards, while a bench will have you grasping the edge behind your hand.

1. Begin by lying down on a floor, preferably a firm but soft area for comfort. Your arms can either by pointing downwards or out, depending on what gives you more stability. If using a bench, then lie down with your head supported and grasp the edge of the bench behind your head.

2. Initiate the movement by bending your knees and engaging your abs. Your knees should come directly over the hips, with your lower legs being parallel to the floor. Maintain a straight, aligned back against the floor, while allowing for a natural curve in the lower back.

3. With an exhalation, engage the abs in order to curl the hips and knees towards your chest. However, only your hips should come off the ground with your knees remaining at the same angle throughout. You will reach the top of the movement when you can’t crunch any further without your back coming off of the surface.

4. In a controlled fashion, take a breath and slowly return to the position where your lower legs are parallel to the floor and your knees are directly over your hips. This is the starting position, and coming back counts as one rep.

5. Maintain the 90-degree angle with your knees, and remember to go slowly and keep your core engaged throughout the whole exercise. Repeat for the desired number of reps, but going for 3 sets of around 8 reps is a good rule of thumb.

Brushing Up on Form

As a core exercise that can have ramifications on your spinal health, it’s important to do this exercise to the best of your ability.

Like with most exercises, momentum is usually cheating (unless you’re doing some explosive movements). The slower you go with the reverse crunch, the more benefits you’ll reap. If you go too fast on the way up, the engagement in your abdominals is going to suffer—and that’s the entire reason you’re doing this exercise. Don’t expect it to be as easy as crunches, and don’t go chasing numbers.

But it’s just as important, if not more important, to lower yourself back down slowly as well.

At the bottom of the movement, don’t let your body “drop” and have the knees go in front of the hips. This is one of the more common mistakes with this movement and it leads to hyperextension of the lower back—otherwise known as arching, which is a big no-no.

If you do the movement in a slow and controlled manner, then there shouldn’t be any arching of the back at the bottom of the movement. If you do find yourself going too far, it might mean that you need to strengthen the core more before trying the reverse crunch out again. 

Another common mistake is not bringing the knees up towards the ceiling before continuing the movement. Unlike the standard crunch which depends on the lumbar spine for the lift, the reverse crunch is meant to use the thoracic spine and rib cage—which it can’t do if you don’t properly raise the knees or go too fast.

Following the above is what’ll get your abs engaged more effectively and produce greater results—i.e., a six-pack. 

A good tip to help with the exercise is placing a foam roller between your calves and your hamstrings, right in the bend of your knee. If you squeeze the roller and really dig your calves into it, it’ll help by producing more tension in your body which will in turn help to stabilize you throughout the motion.

And the more stable you are? The more your abs will be engaged and the better results you’ll get from doing the reverse crunch. It’ll also help when it comes to cleaning up your form.

Reverse Crunch Variations

While the reverse crunch is already a twist on the traditional version, we can go a step further and add even more variety.

Since this is a bodyweight exercise, it’s not as easy to make it easier if you’re having issues—you can’t just take a plate off. And while it’s not necessarily recommended for those you can’t perform at least a few full reps, it is possible to make reverse crunches easier if you are on the cusp of not-yet-ready but crunches are too easy.

It is important to maintain the form (knees above hips), but you can do the exercise with a limited range of motion. This means not raising your hips completely off the surface you’re using during each rep. However, remember not to make things easier on the other end—don’t let your lower body “drop” and end up arching your back. 

And what if the reverse crunch is becoming too easy for you?

Taking Your Core Workout to the Next Level

Well, first of all, congrats on the six-pack—but we’re not done yet. Try adding a crunch into the movement as well. We know we’ve ripped on regular crunches in the past few paragraphs, but if done correctly with proper form, there’s not much to worry about if you don’t overdo it.

Once you reach the bottom of the exercise with your knees still above the hips, engage your abdominals once again, but this time bring your shoulders and head up towards your knees—but still maintain the correct positioning. 

Want to go a step further? Either sit down on a chair or even try it on an incline bench. Especially when it comes to the incline bench variation, you’ll be working against gravity on another level. Your hip flexors will be challenged while improving your stability and mobility in the lower back region. With your body on an incline, the range of motion increases in a way that places more tension on the abs.

And depending on the incline of the bench and your weight, your grip is also going to have an amazing workout.

And what’s the natural progression from that? Hanging reverse crunches of course.

Just make sure that you’re doing it as a reverse crunch and not a leg raise. That means keeping your knees bent at 90-degrees and in line with your hips at the very bottom of the movement—a much more difficult task when you’re hanging from a pull-up bar. 

Leg raises, on the other hand, have you starting with your legs downward and then lifting them up. The leg raise is arguably not an abdominal movement at all (even if you might feel it in the area), so if abs are the name of the game, make sure it’s a reverse crunch and not a leg raise.

Sculpting the Abs

Everyone knows that we all have abs if we’re skinny enough, but we’re aiming for more than just abs. 

While you want to keep your body fat percentage in check, the reverse crunch is meant to build strength and aesthetics in your abdominals and core—and it definitely won’t be able to do that if you’re not properly taking care of yourself.

You can’t out-train a bad diet, and your abs can’t shine through a bad diet either. You’re going to have to back up your workouts with the right ratio of protein, carbs, and fats while also making sure you’re getting enough micronutrients and sleep. 

If you want to get an edge on the competition (or your own goals), consider taking supplements to get that shredded six-pack torso and the physique of a Greek sculpture. Putting all of this together and building habits around it is the only way to get results that are both healthy and will get you through whenever the going gets particularly tough.