Oblique Crunches Floor
The Oblique Crunches Floor are a bodyweight core exercise focused on strengthening the oblique muscles through controlled trunk rotation.
Oblique Crunches Floor
Muscles Worked: Oblique Crunches Floor
Oblique crunches on the floor mainly train your abs, especially the obliques on the sides of your waist. Those muscles shorten to curl your upper body and twist slightly, which is why you feel the work more on one side than a regular ab crunch. Your deeper core muscles help keep you from rocking or using momentum, so the move stays focused on your midsection. Research comparing isolated and integrated core exercises found higher activation in some trunk muscles during isolated core work under the tested conditions (Saeterbakken et al., 2019).
Technique and form
How to perform the Oblique Crunches Floor
- Lie flat on your back with knees bent and feet flat on the floor, hip-width apart.
- Place your hands lightly behind your head with elbows pointing outward, being careful not to pull on your neck.
- Draw your navel toward your spine to engage your core muscles and stabilize your lower back against the floor.
- Exhale as you lift your head, shoulders, and upper back off the floor while simultaneously rotating your torso to bring your right elbow toward your left knee.
- Your left knee should bend toward your chest while your right leg remains in the starting position with foot on the floor.
- Inhale as you slowly return to the starting position, controlling the movement.
- Repeat the movement on the opposite side, bringing your left elbow toward your right knee as it bends toward your chest.
- Continue alternating sides in a controlled manner, focusing on the twisting motion that targets the oblique muscles.
Important information
- Keep your movements slow and controlled rather than using momentum to complete the exercise.
- Maintain space between your chin and chest throughout the movement to avoid strain on your neck.
- Focus on the rotation coming from your core rather than simply lifting your shoulders.
- If you experience lower back discomfort, try placing your feet closer to your buttocks or modify by keeping both feet on the floor.
Is the Oblique Crunches Floor good for muscle growth?
Yes. Oblique crunches on the floor can help build muscle in your side abs when you do enough hard reps and keep tension on the target area. Isolated core work can be useful when your goal is to train the trunk muscles directly, and isolated core drills have shown higher activation in some trunk muscles than integrated movements under tested conditions (Saeterbakken et al., 2019).
- Direct oblique tension — This move puts most of the effort on the muscles that bend and twist your torso, so it is a simple way to give your side abs extra work after bigger lifts. That makes it useful if your main goal is more visible core development rather than just general bracing strength.
- Easy to feel working — Because you are on the floor with no equipment, it is easier to slow down, shorten the range slightly, and keep the tension where you want it. If you lose that feeling and start yanking with your neck or swinging, the set stops training the target well.
- Low fatigue, easy volume — Oblique crunches do not drain you like heavy compound lifts, so you can add more weekly core volume without wrecking recovery. That is helpful if you already squat, hinge, and press hard but still want extra ab work.
- Good pairing with other core drills — This exercise trains trunk bending and a bit of twisting, while moves like the crunch-floor hit the front abs more evenly and the side-plank challenge your core by making it resist movement. Using more than one pattern usually builds a more complete midsection. Free-weight and stability-ball exercises can also produce substantial trunk muscle activity in selected movements, though that study did not directly compare them with focused floor crunches (Nuzzo et al., 2008).
Programming for muscle growth
Do 2-4 sets of 12-25 reps per side with 30-60 seconds rest, 2-4 times per week. Use slow reps and stop each set when the burn is in your obliques, not your neck or hip flexors. Once 25 clean reps per side feels easy, add a pause at the top or increase total weekly sets to keep progressive overload moving.
Alternative Exercises
Built for progress
Take the guesswork out of training
Create personalized AI-powered workout plans that evolve with you. Train smarter, track every rep and keep moving forward, one workout at a time.
FAQ - Oblique Crunches Floor
Oblique crunches primarily target the internal and external oblique muscles that run along the sides of your torso. They also engage the rectus abdominis (six-pack muscles) and transverse abdominis as secondary muscles.
Lie on your back with knees bent, feet flat on the floor. Place your hands lightly behind your head, then lift your shoulders while rotating to bring your right elbow toward your left knee. Return to starting position and repeat on the opposite side, keeping your movements controlled throughout.
For an easier version, perform the movement with a smaller range of motion or keep your feet wider apart for more stability. To increase difficulty, extend one leg straight while performing the crunch, add a pause at the top of each rep, or hold a weight plate or medicine ball against your chest.
Avoid pulling on your neck with your hands—your abs should do the work, not your arms. Don't rush through repetitions with momentum; maintain controlled movements. Also, prevent lower back strain by keeping your lower back pressed into the floor throughout the exercise.
Include oblique crunches 2-3 times per week with at least 24 hours of rest between sessions to allow for muscle recovery. Start with 2-3 sets of 10-15 repetitions per side and gradually increase volume as your core strength improves.
Scientific References
The effects of performing integrated compared to isolated core exercises.
Saeterbakken AH, Chaudhari A, van den Tillaar R et al. · PloS one (2019)
Trunk muscle activity during stability ball and free weight exercises.
Nuzzo JL, McCaulley GO, Cormie P et al. · Journal of strength and conditioning research (2008)
Sources are peer-reviewed academic publications from PubMed.
Oblique Crunches Floor
Thank you for your feedback!
Thank you for your feedback!