Sit-ups
Sit-ups are one of the most recognizable ab exercises, training the core through a full range of motion with zero equipment needed.
Equipment
Bodyweight
Difficulty
beginner
Sets & reps
3 sets · 15-20 reps
Muscles worked
Abs, Hip flexors
A classic core exercise that lifts the entire torso off the floor, training the abs through a longer range of motion than a crunch.
How to do it
- Lie on your back with your knees bent and feet flat on the floor.
- Cross your arms over your chest or place your hands behind your head lightly.
- Engage your abs and curl your torso up until you're sitting upright.
- Lower back down under control to the starting position.
- Keep the movement smooth rather than using momentum to snap up.
Coaching tips
- Avoid pulling on your neck with your hands — let your abs do the work.
- Exhale as you sit up to help engage your core more fully.
- If you feel this mostly in your hip flexors instead of your abs, try crunches instead for more direct ab isolation.
Common mistakes
- Yanking on the neck with clasped hands, straining the cervical spine.
- Using momentum to swing up rather than controlled ab engagement.
Frequently asked questions
Sit-ups or crunches — which is better for abs?
Crunches isolate the abs more directly with less hip flexor involvement; sit-ups train a longer range of motion. Both have a place in a core routine.
Start tracking your workouts free
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