Core · Spinal flexion

Hanging Knee Raise

The hanging knee raise is a core exercise where you hang from a pull-up bar and bring your bent knees up toward your chest. It trains the abs and hip flexors through a controlled curl of the pelvis, and it is the usual stepping stone before straight-leg hanging raises.

Also known as: Hanging knee tuck, Knee raises on a pull-up bar, Captain's chair knee raise alternative

Muscle group: Core
Movement pattern: Spinal flexion
Type: Isolation
Equipment: Pull-up bar
Difficulty: Intermediate

What muscles does the hanging knee raise work?

Primary movers

Rectus abdominis
Hip flexors

Assisting muscles

Obliques
Forearm flexors
Latissimus dorsi
Transverse abdominis

The rectus abdominis is the main target, but only if you curl your pelvis up. When the hips tilt backward at the top, the abs shorten and do real work. If you only lift the knees, the hip flexors take over and the abs act as passengers.

The hip flexors, mainly the iliopsoas and rectus femoris, raise the thighs toward your torso. They work hard in this exercise, and a bent-knee version shortens the lever so they can move your legs without the extra load that straight legs create.

Your lats, forearms and grip hold you on the bar, and the obliques and deep abs stop you swinging. Controlling the lowering phase is what makes the exercise honest, because it forces the abs to resist the pull of the legs as they straighten.

Hanging can be hard on the grip and shoulders for beginners. Ab straps take the grip out of the equation and let you rest your elbows in the loops, while a plain bar works fine if you keep your shoulders active and your neck relaxed.

How to do the hanging knee raise

Setup

1
Hang from a pull-up bar with an overhand grip, or slide your upper arms into ab straps so your elbows rest in the loops.
2
Let your legs hang straight down, with your feet together.
3
Brace your core, pull your shoulders away from your ears and stop any swinging.
4
Settle into a still hang before you start the first rep.

Execution

1
Bend your knees and start to lift them toward your chest.
2
Think about curling your hips up toward your ribs, not just raising your knees.
3
Pause briefly when your knees reach chest height and your lower back rounds slightly.
4
Lower your legs slowly until they hang straight again, without letting your body swing.
5
Exhale as you raise your knees and inhale as you lower them.
6
Repeat for the desired number of repetitions, resetting your hang if you start to swing.

Common hanging knee raise mistakes

Swinging the legs up

Momentum does the work and the abs get little tension.

The fix: Pause in the dead hang between reps and lift under control.

Stopping at hip height

A short range works the hip flexors more than the abs.

The fix: Bring your knees all the way to your chest and curl your pelvis.

Dropping the legs quickly

You lose the lowering phase, which is where much of the control is trained.

The fix: Take two to three seconds to lower the legs until they hang straight.

Shrugging up to the ears

A passive shoulder position strains the neck and shoulders.

The fix: Pull your shoulder blades down gently and keep your neck long.

How many sets and reps?

Goal	Sets	Reps	Load	Rest
Hypertrophy	3–4	8–15	Bodyweight, 1–2 reps in reserve	60–90 s
Strength	3–4	6–10	Slow lowering, add a pause at the top	90 s
Beginner	2–3	5–8	Ab straps, short range if needed	60–90 s

Use hanging knee raises near the end of a session as direct ab work, or on pull day when your grip is still fresh. Once you can do 12 to 15 clean reps without swinging, try straight-leg hanging raises.

Running the hanging knee raise in your next block? Hercules logs every set, shows last session's numbers before you lift, and suggests when to add weight.

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Frequently asked questions

Do hanging knee raises work the abs or the hip flexors?

Both. Curling your pelvis up at the top shifts more of the work to the abs.

Can I do hanging knee raises without ab straps?

Yes. Hold the bar with an overhand grip instead, and the movement is the same.

How do I stop swinging?

Brace your core, pause in a still hang between reps and raise your knees slowly.

Are hanging knee raises easier than hanging leg raises?

Yes. Bent knees shorten the lever, so they suit most people before straight legs.

Hercules tracks every hanging knee raise you log, shows you last session's numbers before you lift, and flags when your progress stalls.