Decline Crunches and Sit Ups

By: Jeremy Fox, CNC, CPT – Published: August 11, 2021

Everyone wants abs. But I don’t know many people who like doing crunches or sit-ups!

One way to make ab workouts less monotonous is by mixing things up. Or using different variations to shock your abdominals and keep things from getting boring.

Decline crunches (sometimes called sit-ups) are a great ab exercise to add to your ab training arsenal. So I’m going to teach you how to do this exercise with proper form. Plus 3 variations to shred your midsection.

What Are Decline Crunches and Sit-Ups?

Decline crunches and decline sit-ups are ab exercises performed on a decline bench. This puts your body in a downward angle where your head is below your legs.

When compared to traditional floor crunches and sit-ups, the decline position forces you to work more against gravity. In other words, the steeper the angle, the more of your body weight you have to lift.

In addition, your ankles are hooked into footpads on the bench, which keeps your thighs straighter relative to your torso. This engages your lower abdomen more than floor crunches.

Decline Crunches vs Decline Sit-Ups

The terms crunch and sit-up are often used interchangeably. But it’s important to understand the slight differences before doing this exercise so that you can use proper form.

First, a sit-up is when you lift your shoulders off the ground (or bench) to an almost upright position with a relatively straight back. This is probably what you remember from gym class when someone was holding your feet.

Whereas a crunch is when you lift your shoulders just enough to fully contract your abdominals. This results in a more curved back compared to sit-ups. And it also activates your ab muscles to a greater extent.

Basically, you move your body more in a sit-up, but you contract your abs more in a crunch. And you can see this represented in the picture below.

From here on out, I’ll be talking about decline crunches since they are better for building and strengthening your abs. And I assume that’s why you’re here!

Decline Crunches Muscles Worked

As with any crunch, the primary muscles worked during a decline crunch are your rectus abdominis or abs. These are the small rectangular muscles that make up the much sought-after 6-pack.

With certain variations, you can also activate the feather-like muscles along the side of your abdomen. Also known as the obliques. I’ll explain how to target this area in the sections below.

How To Do Decline Crunches

To do decline crunches, you’ll need a decline bench or some other slanted surface. Usually, the decline bench will have padded bars that hold your lower legs in place.

1. Hook your lower legs into the footpads
2. Place your hands on your head or across your chest
3. Lay back until your back just touches the bench
4. Squeeze your abs to lift your shoulders up towards your thighs
5. Repeat for the desired number of reps before dismounting

Decline Crunches Form

With this exercise, it’s important to use perfect form. Here are some additional tips to help you perform this exercise properly. And to get the most activation from your abdominal muscles.

To get the most abdominal contraction, imagine a string connecting your sternum to your navel (light blue line in the image below). When performing the crunch, try to shorten that distance as much as possible.

If you use strict form as described above, you can make your abs fail much faster. And that’s what results in more strength and muscle gains.

Decline Crunch Variations

As I mentioned earlier, there are a few different variations of decline crunches that you can use for targeting specific parts of your abdomen or making the exercise more challenging.

Decline Oblique Crunches

Decline oblique crunches use a twisting motion to involve your side abdominals in the movement. For this reason, they are also called a decline twisting crunch or decline side crunch.

To do this variation, twist your trunk so that your right elbow moves towards your left knee and vice versa. Whichever elbow is forward is the side your obliques will be working.

You can alternate sides on each rep or do multiple reps with each side before switching.

Weighted Decline Crunch

Once you build up your strength on the decline crunch, you may be able to perform 20 reps or more. That’s when it’s time to add extra weights to make the exercise more challenging.

Most often, weight is added by holding a weight plate in front of your chest during the movement. But you can also use a medicine ball, dumbbell, or any heavy object you have laying around.

My YouTube channel has dozens of videos showing you how to do a variety of bodybuilding exercises. You’ll learn how to target and build specific muscle groups in 90 seconds or less. Click HERE to subscribe, or click on the button below!

Reverse Decline Crunch

A reverse decline crunch is when you lay on the decline bench in the opposite direction. With this variation, you’re lifting your legs up instead of your upper body, which works the lower abdominal muscles.

To do this exercise, start by laying with your head at the top of the decline bench. Then grab the foot pads with your hands to hold yourself steady. From this starting position, lift your legs until your hips come off the bench.

10 Tips For Getting Abs

Decline crunches are a great addition to your ab training regimen. But if you really want to get a six-pack, you have to reduce overall body fat.

To do this you need a mix of diet, exercise, and maybe some supplements. So if you want a six-pack sooner, check out my 10 tips for how to get abs faster.

With this information, you’ll be well on your way to reaching your fitness goals. And if you found this exercise tutorial helpful, click on the articles below for more workout tips!