Bent-Knee Hip Raise
The bent-knee hip raise has you lying on your back with your knees drawn up, curling your hips a few inches off the floor using your lower abs instead of your legs. It's a bodyweight move that isolates the abdominals through a small, controlled range, making it a good fit for beginners building ab control before they add straighter-leg or hanging variations.
Why it works
Your abs curl the spine and pelvis toward each other, and most floor ab exercises only train one half of that action: the crunch pulls the ribs down toward the pelvis. The hip raise trains the other half, pulling the pelvis up toward the ribs while the upper body stays still. Keeping the knees bent shortens the lever your abs have to move, which lets you feel the tailbone actually lift off the floor instead of relying on your hip flexors to swing the legs for you.
Set up
- Lie on your back on a mat with your arms flat at your sides, palms down for a bit of extra stability.
- Bring your knees up so your thighs point roughly toward the ceiling and your shins are roughly parallel to the floor.
- Press your lower back gently into the mat before you start the first rep.
How to do it
- Contract your abs to curl your hips off the floor, lifting your tailbone a few inches up and in toward your ribs.
- Keep your knees bent at the same angle throughout the rep, don't let them drift toward your face.
- Hold the top position for a brief moment and feel the squeeze in your lower abs.
- Lower your hips back to the mat under control, stopping before your lower back arches off the floor.
- Reset fully between reps rather than letting the previous rep's momentum carry into the next one.
Form cues
- Lift the hips, not just the knees.
- Move slow, no swinging the legs.
- Keep the lower back pressed toward the mat.
- Small range, real squeeze at the top.
Breathing: Exhale as you curl your hips up, inhale as you lower them back down.
Common mistakes
Swinging the legs to build momentum instead of lifting with the abs.
Fix: Slow the tempo down and start each rep by pressing your lower back into the mat before you curl the hips up.
Letting the lower back arch off the mat as the hips lower.
Fix: Lower only as far as you can control before your back wants to arch, and stop the rep there.
Rocking the knees toward the chest without actually lifting the tailbone.
Fix: Focus on the hips leaving the floor, not just the knees bending further; a small hip lift beats a big knee swing.
Rushing through reps too fast to feel the top contraction.
Fix: Pause briefly at the top of every rep before lowering back down.
How to program it
- Because the only load is your own legs, most people can handle 3 to 4 sets of 12 to 20 reps, 3 to 4 times a week, without much lingering soreness.
- It works best early in an ab-focused segment of your session, before fatigue makes it harder to keep the swing out of the movement.
- It needs almost no space or equipment, so it fits easily as a finisher after your main lifts on a lower body or full body day.
- Once 4 sets of 20 slow reps feel easy, progress by moving to a straight-leg raise rather than adding weight to this version.
Safety notes
- Stop the lowering phase just before your lower back lifts off the mat; letting it arch shifts the strain toward your spine instead of your abs.
- Skip this movement on days your lower back already feels irritated, since the hip-curling motion loads that same region.
Exercise profile
- Force
- Pull
- Mechanics
- Compound
- Category
- Strength
Frequently asked questions
How many reps of bent-knee hip raise should I do?
Twelve to twenty slow, controlled reps for 3 to 4 sets works well for most people. The range of motion is small, so control matters more than chasing a high count.
Why can't I feel this in my abs?
If your lower back arches or your legs swing, your hip flexors and momentum are doing the work instead of your abs. Slow down and press your lower back into the mat before each lift.
Is bent-knee hip raise better than a regular crunch?
They train the same muscle from opposite ends. A crunch pulls the ribs toward the pelvis; the hip raise pulls the pelvis toward the ribs. Most people get more out of doing both than picking just one.
Can I do this without any equipment?
Yes, it's a bodyweight-only movement done flat on the floor or a mat. No equipment is needed at all.