When was the last time you thought about the AbMat?
If you’ve been doing CrossFit for a while, you’ve probably used one. It’s been a staple since the beginning.
But somewhere along the way, people stopped understanding why they’re using it. Programming moved away from it. That little curved piece of foam started collecting dust in the corner of the gym.
And that’s a problem, because the AbMat does something specific and valuable that nothing else quite replicates.
If you’d rather watch and listen to this conversation, you can do that here.
Let’s talk about why this simple tool matters and how you should actually be using it.
Why CrossFit Doesn’t Endorse Much Equipment
First, some context: CrossFit is pretty minimal when it comes to equipment endorsements. We keep things basic — barbells, pull-up bars, rowing machines. The fundamentals.
So when CrossFit does specifically talk about a piece of equipment and includes it in foundational education, there’s a reason. That equipment does something. It works. It provides genuine benefits and results.
The AbMat is one of those pieces of equipment.
The Problem With Regular Sit-Ups
Let’s start with what happens when you do a sit-up without an AbMat.
You’re lying flat on the ground. There’s a gap between your lower back and the floor because of your natural spinal curvature. You start the sit-up, and here’s what happens:
Your back loses contact with the floor pretty quickly. Once that happens, your abdominals stop working dynamically (creating movement) and start working as stabilizers instead. Your hip flexors take over and pull you through the rest of the range of motion.
So, the actual range of motion where your abs are working to create movement? It’s surprisingly small. Basically a crunch.
The rest of the sit-up? Your abs are just holding position while your hip flexors do the work.
That’s not necessarily bad; isometric ab work has value, and hip flexor strength matters. But if you’re doing sit-ups to train your abs, you’re getting a lot less than you think.
What the AbMat Actually Does
The AbMat fills that gap between your lower back and the floor.
Now, when you try to sit up, your lower back is under constant pressure against something. It stays in contact with support throughout the entire movement. And because of that sustained contact, your abdominals can work dynamically through a much larger range of motion.
Instead of losing the ability to create movement once your back leaves the floor, your abs continue to drive the movement all the way up.
In practical terms, the AbMat turns a crunch plus isometric hold into a true full-range sit-up where your abs work dynamically from start to finish.
That’s a fundamentally different stimulus. You’re training the abs differently, through a larger range of motion and more dynamic contractions.
Why Range of Motion Matters (More Than You Think)
One of CrossFit’s core principles is maximizing useful range of motion. And there’s a concept that matters here: new range is weak range.
What does that mean? Any range of motion that isn’t traditionally used is probably a weak range for those muscles.
Think about someone who doesn’t squat deep; the bottom range around their knees is weak because it never gets trained. The same principle applies to your abs.
If your abdominals never contract dynamically past that initial crunch range because your back bottoms out on the floor and your hip flexors take over, that extended range is probably weak.
And why does that matter? More than you might think.
If you’ve ever wrestled, done martial arts, or any sport requiring trunk rotation under load, you know there are situations where you need your abdominal musculature to work past that short initial range. Trying to twist someone off you. Explosive rotation in throwing mechanics. Stabilizing through extended positions.
You don’t want weak ranges of motion in your abdominal capacity — not for performance and not for injury prevention.
The AbMat helps eliminate that weak range by training your abs dynamically through the full movement.
How to Actually Use The AbMat
The AbMat can be used in multiple contexts, but the application matters.
Conditioning Workouts
Think about a workout like Annie: 50-40-30-20-10 reps of double-unders and sit-ups. In this context, you’re using the AbMat and probably anchoring your feet to go as fast as possible. You want every bit of mechanical advantage you can get.
When your feet are anchored and you’re using an AbMat, both your abs and hip flexors work through the full range of motion together. That’s actually ideal; you’re training both muscle groups through complete movement under time pressure.
This is about performance. This is about getting the best time possible.
Targeted Ab Work (Warm-Up or Accessory)
This is where most people should use the AbMat more consistently: slow, controlled ab work as a warm-up or accessory movement.
Here’s the setup:
- Put the AbMat under your lower back.
- Sit in a butterfly stretch position — soles of your feet together, legs bent.
- Lie back until your shoulders touch the floor.
- Sit up in a slow, controlled fashion.
The key thing to watch: Your feet should not move outward, and your knees should not move inward during the movement. When that starts happening, it means you’re recruiting your hip flexors to help pull you up.
The goal is isolated ab work — slow, controlled, maintaining position. This trains your abdominals dynamically through a full range of motion without compensation.
Do this as part of your warm-up or as accessory work after training. Sets of 10-20 reps, focusing on quality over speed.
The Difference Between Training and Practice
Understanding when you’re training versus practicing matters.
When you’re doing Annie or another timed workout with sit-ups, you’re practicing the movement under fatigue. You’re working on efficiency, speed, and maintaining output when tired. Anchor your feet, use the AbMat, and go fast.
When you do slow butterfly sit-ups on the AbMat as a warm-up, you’re training the abdominals specifically. You’re building strength through range of motion. Keep it controlled, no compensation.
Both have value. Just know which one you’re doing and why.
An Introduction to Core Work
If you’re new to CrossFit or working with someone new, the AbMat sit-up is one of the best introductions to direct core work.
It’s accessible, scalable, and teaches body awareness and control. And unlike many ab exercises that only train static stabilization, it builds dynamic strength through movement.
Most of our foundational functional movements train the abdominals primarily as stabilizers — squats, deadlifts, overhead work. They’re working statically to maintain positions.
The AbMat sit-up gives you a different training stimulus: dynamic contraction through a range of motion. That’s a necessary complement to all the static work.
If you’re only training a muscle group isometrically or statically, you’re probably not creating as much strength as you could by also training it dynamically. That principle applies to abs just like it applies to everything else.
Potential for Rehab Applications
Here’s something worth experimenting with: the AbMat might be valuable for people dealing with back pain.
Regular sit-ups are often provocative for back pain. They force your spine through both flexion (rounding at the top) and extension (arching at the bottom). If you have back issues, one or both of those positions probably cause pain.
But with an AbMat, there’s potential to work the abdominals through their range of motion while minimizing painful spinal positions. The support it provides might allow for strengthening the 360-degree musculature around the trunk without aggravating existing issues.
This isn’t medical advice; if you have back pain, work with a qualified professional. But the AbMat’s design suggests it could be a useful tool for building abdominal strength without provoking pain.
Strengthening the entire trunk musculature in a variety of ways — not only statically, but also dynamically — is probably valuable for anyone dealing with back issues.
How To Bring More AbMat Sit-Ups to Your Life
You don’t need to overhaul anything. Just start including AbMat work intentionally.
As a warm-up: 2-3 sets of 15-20 slow butterfly sit-ups before your workout. Focus on control and a full range of motion.
As a finisher: After your workout, spend 5 minutes doing controlled AbMat work. Your abs are already fatigued from stabilizing during the workout; now train them dynamically.
In your accessory work: If you do dedicated core work, include AbMat sit-ups alongside planks, hollow holds, and other ab exercises.
In met-cons, when appropriate: Workouts like Annie, or any workout with sit-ups for time or reps, should use the AbMat.
It doesn’t take much. Just consistent inclusion with intentional purpose.
The Bottom Line
The AbMat is a simple piece of equipment that does something specific and valuable: it allows your abdominals to work dynamically through a full range of motion during sit-ups, rather than becoming stabilizers halfway through the movement.
That creates a different training stimulus; one that complements all the static ab work you’re already doing in squats, deadlifts, and carries.
Use it in conditioning workouts when appropriate. Use it in slow, controlled accessory work to build ab strength through range. Use it as a warm-up tool to activate your core before training.
Just don’t let it collect dust because you don’t understand what it does.
Pull out the AbMat. Put it under your lower back. Get in that butterfly position. Do 20 slow, controlled sit-ups, focusing on using your abs through the entire movement without your feet moving or your knees caving.
Your abs will tell you they’ve been missing this.
About the Author
Stephane Rochet is a Senior Content Writer for CrossFit. He has worked as a Flowmaster on the CrossFit Seminar Staff and has over 15 years of experience as a collegiate/tactical strength and conditioning coach. He is a Certified CrossFit Trainer (CF-L3) and enjoys training athletes in his garage gym.
Comments on The AbMat: Why This Simple Tool Changes Everything About Sit-Ups
0 Comments