The hanging knee raise is among the best exercises for targeting the lower abs while working out your entire core. This exercise also builds excellent forearm and grip strength.

You can perform a hanging knee raise with minimal equipment. All you really need is something to grip and hang from, such as a pullup bar. Some companies make special equipment for performing hanging knee raises as well.

This article breaks down the hanging knee raise, including how to perform the exercise, its benefits and muscles worked, a few common mistakes, and variations to make it easier or harder.

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The hanging knee raise is straightforward to perform.

You should use a pronated, overhand grip, meaning your palms will face away from you when gripping your equipment.

The key to ensuring proper muscle activation is maintaining a neutral pelvis or a slight posterior tilt by activating your lower abs before you lift your knees.

To do this, visualize tilting the top of your pelvis (your hip bones) up toward your bottom ribs and gently squeezing your glutes.

Note that over-squeezing your glutes will prevent you from raising your knees, so only engage enough to prevent your lower back from arching.

You should feel the muscles of your lower stomach just above your hip crease engage as they activate. This should result in a gentle hollowing of the front of your torso.

In short, perform the hanging knee raise with the following steps:

  1. Grip your pullup bar or other equipment with an overhand, pronated grip and start to hang.
  2. Activate your lower abs by tilting your pelvis toward your ribs and engaging your glutes.
  3. Slowly raise your knees upward toward your chest while maintaining braced lower abs and a hollowed position.
  4. Slowly lower your legs to return to the bottom position.
  5. Repeat for the desired number of repetitions.
Summary

The hanging knee raise requires you to hang from a bar and bring your knees toward your chest.

The hanging knee raise offers several great benefits for strength, fitness, and aesthetics.

This exercise targets the entire core and abdominal region, making it a more comprehensive core exercise than other activities like crunches.

The stability required to maintain proper form and control during the hanging knee raise transfers to other activities and movements, including heavy lifts that require bracing, such as squats or deadlifts.

Performing hanging knee raises with proper technique counteracts the tendency of the lower back to arch by strengthening the muscles that oppose this movement.

Reducing the lower back’s tendency to arch is key for safely loading the spine with added weight.

Promoting a neutral spine position by strengthening the core is a key benefit of properly performed hanging knee raises.

Additionally, the fact that you must hang by gripping the bar leads to improved hand and forearm strength, which transfers to other hanging exercises like pullups, as well as functional and athletic activities like climbing.

Finally, due to the intense resistance placed on the abdominal wall by the hanging knee raise, this exercise can promote hypertrophy and muscular development across the entire abdominal area.

When combined with a nutrition plan that promotes fat loss, the hanging knee raise will dramatically increase the size and definition of your six-pack and oblique muscles.

Summary

The hanging knee raise improves core stability, functional abdominal and grip strength, and increases muscular development in the abdominal area.

The hanging knee raise primarily targets the abdominal muscles. This includes several major muscles in the core and abdominal wall.

Research suggests that hanging knee raise variations are especially effective at targeting the rectus abdominis and external oblique (1).

However, the hanging knee raise works a full range of muscles in both the upper and lower body.

In addition to the rectus abdominis and external obliques, the muscles worked include:

  • internal obliques
  • hip flexors
  • forearm muscles
  • shoulder girdle muscles
Summary

The hanging knee raise targets the major muscles in your core and builds forearm, shoulder, and grip strength.

Although hanging knee raises are relatively straightforward, there are two major errors that you should avoid to maximize the benefit of this exercise and minimize injury risks.

Arching your lower back

The most common mistake when performing this exercise is arching in your lower back. This occurs primarily when you fail to activate your lower abdominals and glutes.

The result is an appearance of sticking out your stomach and having a visible arch across your lumbar spine up to your mid-back.

This position deactivates your abs and forces you to rely solely on your hip flexors to lift your lower body weight.

This can lead to overactive hip flexors and reduced core-muscle strength gains, as well as exacerbate low back pain.

When performing the hanging knee raise with an arched lower back, you will likely feel strain at the top of your thighs and possibly lower back. This sensation is a good sign you’re performing the exercise incorrectly.

To avoid this mistake, focus heavily on bringing the front of your pelvis to your ribs and engaging your glutes. When performed properly, you should feel the core muscles across the front of your stomach working throughout the exercise.

If you feel your abs heating up by the end of your set, you’re likely performing the exercise correctly.

Swinging your legs

The second common mistake people make on the hanging knee raise is swinging their legs and using momentum.

While you may be tempted to swing your legs to eke out more repetitions on a given set, this ultimately decreases the amount of work performed and reduces improvements to your core strength.

The momentum from the swing means your abs and core are doing less work because they’re not contracting throughout the duration of the set.

Letting your legs completely swing down from the top position means that your abs are not resisting gravity on the way down, which gives them less total time under tension.

Additionally, the momentum from the swing means your abs do not have to work as hard when they contract as your knees go up because the force of the uncontrolled lowering gives your legs a boost.

As such, high numbers of reps without control are less meaningful in terms of how much work you actually performed.

Instead, focus on controlling the entire range of motion as your knees come up and down.

If you want to add speed, go fast on the way up, pause at the top, and slowly return your knees to the starting position while maintaining contraction.

The total time your abs spend under tension is far more important for core strength than the total number of repetitions performed.

Focus on feeling the contraction throughout the entire range of motion. Do not attempt to cheat your way to high repetitions.

If needed, you can reduce the number of repetitions you perform to ensure control throughout the set.

Summary

The most common mistakes in the hanging knee raise are arching your lower back and excessively swinging your legs.

Although hanging knee raises are an excellent exercise, depending on your current fitness level, you may need to reduce or increase the difficulty to provide appropriate stimulus to your core muscles.

Ideally, you want to use a variation that allows 3 sets of 10–15 repetitions with perfect form. If you cannot get to 10 repetitions, the exercise variation is too challenging.

If you can easily blast through more than 15 repetitions, you should progress to a more difficult variation to ensure continued strength improvements.

The following are three easier and three harder hanging knee raise variations you can use to modify your training program appropriately.

Supine knees-to-chest

In the supine leg raise, you perform a similar movement while lying on your back on the floor.

This trains the same overall movement without the grip component and with less resistance on your knees due to the different angle, allowing you to build up the core strength for the full hanging knee raise.

To perform a supine knees-to-chest:

  1. Begin lying on your back with hands at your sides, palms down, and legs extended.
  2. Brace your abs and lift your feet about 6 inches (about 15 cm) off of the floor.
  3. Maintain braced abdominals and slowly bend your knees to bring them to your chest while keeping your lower legs parallel to the floor.
  4. Reverse the movement by slowly extending your legs.
  5. Repeat for 10 to 15 repetitions. Do not allow your feet to touch the floor between repetitions.

Supine straight-leg raise

The supine straight leg raise is more challenging than the knees-to-chest variation because it creates a longer lever with your legs, resulting in more work for your abdominals.

To perform a supine straight leg raise:

  1. Begin lying on your back with hands at your sides, palms down, and legs extended.
  2. Engage your abs and lift your feet about 6 inches off the floor, without arching your back.
  3. Maintain braced abdominals and keep your legs straight as your lift your feet until your legs are perpendicular to the floor.
  4. Reverse the movement by slowly lowering your legs. Keep them straight throughout the entire duration of the movement. Keep your head down the entire time.
  5. Repeat for 10–15 repetitions. Do not allow your feet to touch the floor between repetitions.

Dead hang from a bar

The dead hang from a bar will help build your static grip strength to allow you the necessary endurance in your forearms to perform full sets of hanging knee raises.

To perform a dead hang from a bar:

  1. Grip a pullup bar with a pronated, overhand grip.
  2. Based on your equipment setup, step off of your box or lift your feet off of the ground to hang from the bar.
  3. Brace your core by squeezing your lower abs and imagining you’re gently bringing your lower ribs to the top of your pelvis.
  4. Engage your quads and flex your feet. This should result in your feet being a few inches in front of you and the entire front of your body activated.
  5. Hold this position for as long as possible. Work towards 3 sets of 30-second holds with 30 seconds of rest in between.

Once you can comfortably hang for 30 seconds and perform sets of 15 supine leg raises, you’re ready to begin hanging knee raises.

Hanging leg raise

The hanging leg raise is a harder variation of the hanging knee raise.

The main difference is that instead of bending at the knee and keeping your lower legs perpendicular to the floor, you keep your legs straight and raise them until they’re parallel to the floor and straight out in front of you relative to your hanging position.

To perform the hanging leg raise:

  1. Grip your pullup bar or other equipment with an overhand, pronated grip and start to hang.
  2. Activate your lower abs by tilting your pelvis toward your ribs and engaging your glutes.
  3. Keep your legs straight and slowly raise them upward until they’re parallel to the floor.
  4. Slowly lower your legs to return to the bottom position.
  5. Repeat for the desired number of repetitions.

Weighted knee raise

The weighted knee raise requires you to attach additional resistance to your ankles while performing the hanging knee raise.

You can use ankle weights on your feet or even pinch a dumbbell between your feet. Just be sure the floor beneath you is clear.

To perform a weighted knee raise:

  1. Place a dumbbell under a pullup bar, or attach ankle weights to your feet.
  2. Grip your pullup bar or other equipment with an overhand, pronated grip and start to hang.
  3. Pick up the dumbbell with your feet by pinching the handle between your inside foot arches. The dumbbell should be vertical relative to the floor, allowing the top end to rest on the tops of your feet.
  4. Activate your lower abs by tilting your pelvis toward your ribs and engaging your glutes.
  5. Slowly raise your knees upward toward your chest while maintaining braced lower abs and a hollowed position and keep the dumbbell pinched between your feet.
  6. Slowly lower your legs to return to the bottom position.
  7. Repeat for the desired number of repetitions.

The weighted knee raise allows you to progress this exercise by increasing the weight.

Toes-to-bar raise

The hanging toes-to-bar raise is the most advanced variation of the hanging knee raise.

In this exercise, you perform a hanging straight-leg raise using a full range of motion and bringing your feet all the way to the bar.

The top position looks like a pike and requires substantial core strength, as well as hamstring and trunk flexibility, to perform.

To perform the toes-to-bar raise:

  1. Grip your pullup bar or other equipment with an overhand, pronated grip and start to hang.
  2. Activate your lower abs by tilting your pelvis toward your ribs and engaging your glutes.
  3. Keep your legs straight and slowly raise them upward until your feet contact the bar.
  4. Slowly lower your legs to return to the bottom position.
  5. Repeat for the desired number of repetitions.

Note that you may need to improve your hamstring flexibility to perform this exercise even if your core strength allows you to perform a full toe-to-bar movement.

Summary

The hanging knee raise has several modifications and progressions to customize the exercise for various fitness levels.

The hanging knee raise is an efficient and effective core exercise that increases functional strength, muscular development, and control in your abdominal muscles.

This exercise is great for improving grip strength since you’re hanging by your own grip throughout each set.

Regardless of your current fitness level, you can add a hanging knee raise variation to your fitness routine to reap the benefits of this exercise and progress toward the next variation of this exercise.

Add 3 sets of 10–15 repetitions of the hanging knee raise or a variation to the end of your upper- or lower-body routine and expect to see improvements in your core within just a few weeks.