Bent Knee v Sit Up Advanced
The bent knee V sit-up advanced is an intense bodyweight core exercise targeting the abdominals. It builds on the standard variation by emphasizing explosive contraction and peak hold, demanding greater core strength and control.
How to do it
- Lie flat on your back with arms extended overhead and legs straight.
- Explosively contract your core to simultaneously raise your torso and bring your bent knees to your chest.
- Reach your hands past your knees at the top, fully compressing the abs.
- Hold the peak contraction for a moment before slowly lowering back to the starting position.
- Repeat for the desired number of repetitions with controlled movement throughout.
Form cues
- Keep your lower back pressed into the floor.
- Exhale sharply as you crunch your torso upward.
- Control the descent without letting your shoulders drop abruptly.
- Reach past your knees to maximize abdominal compression.
Breathing: Exhale forcefully as you rise into the V-sit position, and inhale slowly as you lower back down to the floor.
Common mistakes
- Using momentum instead of muscle control to swing up, which reduces the work done by your abs.
- Arching your lower back at the bottom of the movement, which can strain your lumbar spine.
- Pulling on your neck with your hands, which leads to unnecessary upper body tension.
Muscles worked
Primary: abs. Secondary: hip flexors, obliques.
Suggested sets & reps
Get fitter
3 sets × 10–12 reps, rest 60 s
Lose weight
3 sets × 10–15 reps, rest 45 s
Build muscle
3–4 sets × 8–12 reps, rest 60 s
Easier, harder & alternatives
Make it harder
Alternatives
Take care if…
- If you feel sharp or pinching pain in your lower back, ease off and choose a gentler core option.
General educational guidance, not medical advice. Stop on sharp pain and check with a qualified professional if unsure.
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Start free →Frequently asked questions
Why do I feel this exercise in my hip flexors?
Hip flexors often take over if your abdominal strength tires out or if you lift your legs too fast. Focus on curling your upper body using your abs first.
How often should I do advanced V-sit ups?
2 to 3 times per week is plenty for recovery and strength building, as intense core work requires rest days.
What should I do if my lower back hurts?
Stop immediately. Lower back pain usually means your core fatigued and your spine lost support. Try a regression like a half V-sit up.