Exercise Library / Sit-up
Sit-up
The original ab builder — full range, from floor to upright.
Muscles worked
Primary Abs
Secondary Hip Flexors
Tap a muscle to explore it on the interactive muscle map.
How to do it
- Lie back, knees bent, feet flat and hip-width apart.
- Cross your arms over your chest or keep fingertips at your temples — don’t pull your neck.
- Exhale and curl up one segment at a time until your chest nears your knees.
- Keep your feet planted; don’t let them lift for momentum.
- Control the way back down — that half of the rep counts too.
Common mistakes
- Flopping back down. Collapsing to the floor wastes the eccentric, which is half of what builds the abs.
- Yanking the neck. Pulling on your head strains the cervical spine and steals work from the abs.
- Feet flying up. If the feet lift, momentum from the hip flexors is doing the sit-up, not your core.
What the camera coach watches
These are the exact checks FitFormBuddy runs on every rep of sit-up — and what it says when you drift:
- Lowering speed“control the way back down”
Get real-time form cues on this exercise
FitFormBuddy watches through your camera and coaches you mid-set — reps counted, mistakes called out as they happen.
