Sit-ups
Sit-ups are a foundational bodyweight abdominal exercise that involves fully raising the torso from the floor. Unlike crunches, the full sit-up range of motion also engages the hip flexors and is commonly used in fitness testing and core conditioning.
How to do it
- Lie flat on your back with knees bent, feet flat on the floor, and hands behind your head.
- Engaging your core, curl your entire torso up toward your knees.
- Continue until your upper body is fully upright.
- Slowly lower yourself back down to the starting position.
- Repeat for the desired number of repetitions.
Form cues
- Keep your feet flat on the floor throughout the movement.
- Engage your abdominal muscles before you start lifting.
- Exhale as you curl your torso upward toward your knees.
- Lower yourself back down with control rather than dropping.
Breathing: Exhale steadily as you curl your torso up, and inhale as you lower yourself back to the floor.
Common mistakes
- Pulling on your neck with your hands, which can cause unnecessary strain.
- Using momentum to swing up, reducing the work done by your core.
- Allowing your feet to lift off the floor, which shifts focus away from your waist.
Muscles worked
Primary: abs. Secondary: hip flexors, obliques.
Suggested sets & reps
Get fitter
3 sets x 10-12 reps, rest 60 s
Lose weight
3 sets x 12-15 reps, rest 45-60 s
Build muscle
3 sets x 8-12 reps, rest 60 s
Easier, harder & alternatives
Take care if…
- If you feel 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?
It is generally better to keep your feet unanchored so your core does rather than your hip flexors pulling you up.
Why do I feel this in my lower back?
Feeling it in your lower back often means your hip flexors are taking over or you are using momentum. Slow down and focus on curling the spine.
How often can I do sit-ups?
2 to 3 times per week is plenty for recovery and strengthening.