Half Sit Ups
Half sit ups are a beginner-friendly bodyweight ab exercise that targets the abs through a partial range of motion. By stopping midway, the movement maintains continuous tension on the abdominal muscles while reducing strain on the lower back.
How to do it
- Lie flat on your back with knees bent, feet flat on the floor, and hands placed behind your head.
- Engage your core and curl your upper body upward until your torso reaches a 45-degree angle.
- Pause briefly at the halfway point, keeping your lower back in contact with the floor.
- Slowly lower your torso back to the starting position.
- Repeat for the desired number of repetitions.
Form cues
- Keep your lower back pressed flat into the floor throughout the movement.
- Exhale as you curl your torso upward to the halfway point.
- Keep your neck relaxed and avoid pulling on your head with your hands.
- Pause briefly at the top to maintain continuous muscle tension.
Breathing: Exhale as you curl upward to contract your abs, and inhale slowly as you lower back down.
Common mistakes
- Pulling on the neck with hands can cause unnecessary strain on the cervical spine.
- Using momentum to swing up reduces the workload on the abdominal muscles.
- Lifting the lower back off the floor shifts tension away from the core and toward the hip flexors.
Muscles worked
Primary: abs. Secondary: hip flexors, obliques.
Suggested sets & reps
Get fitter
3 sets × 10–12 reps, rest 60 s
Lose weight
3–4 sets × 12–15 reps, rest 45–60 s
Build muscle
3 sets × 8–12 reps with a slow tempo, rest 60–90 s
Easier, harder & alternatives
Take care if…
- If you feel sharp lower back discomfort, ease off or choose a gentler core movement.
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
Should my feet be held down during half sit ups?
No, it is generally better to keep your feet flat on the floor naturally to engage your core without assistance from anchoring equipment.
Why do I feel this exercise in my neck?
Neck strain usually happens when you pull your head forward with your hands. Focus on lifting with your chest and core while keeping your hands resting lightly behind your ears.
How many times a week should I do half sit ups?
2 to 3 times per week is a great starting point for beginners, allowing your abdominal muscles time to recover between sessions.