Ab Tuck
- Target muscle
- —
- Equipment
- Body weight
- Body part
- Waist
- Type
- Strength
The ab tuck is a bodyweight core exercise that targets the abdominals (rectus abdominis), with the hip flexors assisting as you draw your knees toward your chest. Done seated on the floor or the end of a bench, it trains spinal flexion and core control with no equipment beyond your own body.
How to do the Ab Tuck
- 1Sit on the floor or the edge of a bench with your torso leaning back slightly and your hands resting beside your hips for balance.
- 2Brace your core and lift both feet off the floor, balancing on your sit bones with your knees bent and shins roughly parallel to the ground.
- 3Extend your legs out in front of you without letting your feet touch the floor, lowering your upper body back at the same time.
- 4Pause briefly in the extended position, keeping your core tight and your lower back from rounding excessively.
- 5Draw your knees back toward your chest while crunching your torso up, squeezing your abs as the knees and chest meet.
- 6Control the tuck at the top, then reverse smoothly into the next rep.
- 7Complete your reps, then lower your feet to the floor and sit up to finish.
Form tips
- Move at a controlled tempo and let the abs, not momentum, drive each tuck.
- Exhale as you pull your knees in and contract your core; inhale as you extend.
- Keep a slight brace through your midsection so your lower back does not overarch when your legs extend.
- Limit your range to what you can control if your hip flexors take over or your back rounds.
Common mistakes
- Using momentum to swing the legs in and out, which takes tension off the abs and reduces the training effect.
- Letting the lower back round hard at the bottom, which stresses the spine instead of loading the core.
- Pulling mostly with the hip flexors rather than crunching the torso, so the abs do little of the work.
- Holding the breath through each rep, which limits core bracing and makes the movement feel harder than it should.
Frequently asked questions
What muscles does the ab tuck work?
It mainly works the abdominals (rectus abdominis) through spinal flexion, with the hip flexors assisting as you draw your knees toward your chest. It is a bodyweight movement, so no equipment is needed.
Is the ab tuck good for beginners?
Yes. It is a bodyweight exercise you can scale by keeping the knees more bent and the range shorter, then progressing to a fuller leg extension as your core gets stronger.
How many sets and reps should I do?
A sensible starting point is 3 sets of 10–15 controlled reps. Add reps before adding speed, since control is what keeps tension on the abs.
Why do I feel the ab tuck more in my hip flexors than my abs?
That usually means you are pulling with the legs and not crunching the torso. Shorten the range, focus on curling your ribcage toward your hips, and slow the tempo so the abs lead the movement.
