What is the difference between an Oblique Crunch and a Cross-Body Crunch?

The Oblique Crunch is done lying on your side and bends the trunk sideways with no twist. The Cross-Body Crunch is done on your back and adds rotation by bringing one elbow toward the opposite knee, so it mixes forward curling with twisting.

Will oblique crunches get rid of love handles?

No, not on their own. In a six-week trial with healthy, sedentary adults, seven abdominal exercises done five days a week did not reduce abdominal fat or the skinfold above the hip bone, although abdominal endurance improved. Losing fat around the waist comes from overall diet and activity, while oblique work builds the muscle underneath.

Should I do oblique crunches or side planks?

Both have a place. The Oblique Crunch trains the obliques to bend the trunk sideways, while the Side Plank trains them to hold the trunk straight against gravity and also works the shoulder and hip, so many programs use one of each.

Why can I only lift my shoulder a few inches off the floor?

That is normal, because the spine only bends a limited amount to the side and the bottom hip stays on the floor. If you are rising much higher, your legs are probably lifting or your torso is rolling back.

How many reps should I do?

Two to three sets of 10 to 15 controlled reps on each side is a common starting point. Once that feels easy, add a pause at the top or move to a loaded side bend rather than piling on more reps.

Oblique Crunch

What Is the Oblique Crunch?

Oblique Crunch is an isolation exercise that primarily targets the core, specifically the obliques along the side of the waist, and also engages the rectus abdominis and the lower back muscles that bend the spine sideways. It is a beginner-level movement done lying on your side on the floor with no equipment, curling the upper body sideways so the ribs move toward the top hip.

The name is used loosely, and this page covers the side-lying version, where the trunk bends to the side without twisting. That sets it apart from the Cross-Body Crunch, which is done on your back and rotates one elbow toward the opposite knee, and from the standard Crunch, which curls the trunk forward and puts most of the work on the rectus abdominis. Because the obliques on the top side shorten to lift the torso against gravity, they do most of the work, and each side is trained separately, which makes it easy to notice and even out a weaker side.

It is usually programmed as accessory core work near the end of a session or in a bodyweight circuit, done for controlled reps on each side. It pairs well with the Side Plank, which trains the same muscles to hold the trunk straight rather than bend it. Crossing the arms over the chest makes each rep easier, and a pause at the top makes it harder. When bodyweight reps become easy, loaded side bending such as the Dumbbell Side Bend, the Cable Side Crunch or the Exercise Ball Side Bend is the next step.

The movement suits beginners and anyone who wants oblique work at home with nothing but a mat. The range is short, so the mind-muscle connection genuinely matters here: think about drawing the bottom of the ribs toward the top of the hip bone rather than lifting the head. If the full version is hard to control, build trunk control first with the Plank and the Dead Bug and keep the arms crossed on the chest until the reps stay smooth.

Muscles Worked

MuscleActivation

External Oblique: Primary
Rectus Abdominis: Medium
Erector Spinae: Low
Sternocleidomastoid: Low
Gluteus Medius: Minimal
Rectus Abdominis (Lower): Minimal
Tensor Fasciae Latae: Minimal

Instructions

Lie on your side on a mat with your legs stacked, knees bent and hips slightly bent so your thighs angle forward.
Stack your hips and shoulders so your body faces straight ahead rather than up toward the ceiling.
Place your top hand lightly behind your head with the elbow pointing up, and rest your bottom arm across your stomach.
Start with your head resting near the floor and your neck in line with your spine.
Brace your core, exhale and lift your top shoulder and ribs up toward your top hip, bending your torso sideways off the floor.
Keep your hips and legs on the floor and stacked, and lift only as far as the side of your waist can shorten.
Pause briefly at the top without pulling on your head.
Inhale and lower your torso under control until your head returns to the floor.
Complete all reps on one side, then switch sides.

Common Mistakes

Pulling on the head
Yanking the head up with the top hand strains the neck and lets the arm do work the obliques should be doing.
Leading with the chin
Craning the head sideways makes the rep feel bigger while the waist barely moves, so think about lifting the ribs instead.
Rolling onto the back
Letting the shoulders or hips roll backward turns the side bend into a twisting forward crunch and takes tension off the obliques.
Lifting the legs
Raising the legs or hiking the top hip to get higher swaps the trunk work for hip movement, so keep the legs heavy on the floor.
Bouncing through reps
Dropping back to the floor and rebounding uses momentum instead of muscle, so lower each rep under control.

Injuries

Oblique Crunch is a low risk exercise when performed with proper technique. The neck takes the most strain, either when the top hand pulls the head up or when the head and chin lead the movement instead of the ribs. The lower back can get irritated in people whose back pain flares with side bending, and lying on a hard floor puts pressure on the bottom hip and shoulder.

Keep the fingertips resting lightly behind your head with the elbow pointing up, lead with the side of the ribs, and move slowly through a short range without bouncing. Use a mat or folded towel under the bottom hip, and keep the hips and shoulders stacked so the trunk bends sideways rather than twisting.

To make it easier, cross both arms over your chest and lift only as high as you can control. To progress, pause for two or three seconds at the top, then move on to loaded side bending such as the Dumbbell Side Bend or the Cable Side Crunch, or to holds like the Side Plank.

Stop the set if you feel sharp or radiating pain in the lower back, pain or pinching in the neck, or pain at the bottom hip. Anyone with a current back injury should get clearance from a clinician before adding side bending to their routine.

Overview

Primary Focus: Core
Equipment: Body weight
Modality: Strength
Difficulty: Beginner

Alternative Exercises

Other Names for the Oblique Crunch

The Oblique Crunch is also known as:

Side Crunch
Lying Side Crunch

Frequently Asked Questions

Q: What is the difference between an Oblique Crunch and a Cross-Body Crunch?: The Oblique Crunch is done lying on your side and bends the trunk sideways with no twist. The Cross-Body Crunch is done on your back and adds rotation by bringing one elbow toward the opposite knee, so it mixes forward curling with twisting.
Q: Will oblique crunches get rid of love handles?: No, not on their own. In a six-week trial with healthy, sedentary adults, seven abdominal exercises done five days a week did not reduce abdominal fat or the skinfold above the hip bone, although abdominal endurance improved. Losing fat around the waist comes from overall diet and activity, while oblique work builds the muscle underneath.
Q: Should I do oblique crunches or side planks?: Both have a place. The Oblique Crunch trains the obliques to bend the trunk sideways, while the Side Plank trains them to hold the trunk straight against gravity and also works the shoulder and hip, so many programs use one of each.
Q: Why can I only lift my shoulder a few inches off the floor?: That is normal, because the spine only bends a limited amount to the side and the bottom hip stays on the floor. If you are rising much higher, your legs are probably lifting or your torso is rolling back.
Q: How many reps should I do?: Two to three sets of 10 to 15 controlled reps on each side is a common starting point. Once that feels easy, add a pause at the top or move to a loaded side bend rather than piling on more reps.