I did 100 hanging knee tucks every day for a week — here's what happened to my body and core

Woman performing hanging knee tucks
(Image credit: Getty Images)

When you want to work your core, back, and arms in one go, then a hanging knee tuck needs to be your go-to move. This seemingly simple bodyweight exercise requires just a pull-up bar and your weight but it can elicit some serious burn. 

I’m all for an abs workout and love anything that sets my core muscles on fire. So why would I not agree to a hanging knee tuck challenge? For this, I opted to do 100 hanging knee tucks every day for a week. 

I’ve done a week of 100 chin-ups every day in the past and I’ve conquered the mighty pull-up, but 100 hanging knee tucks every day for a week isn’t something I've even touched on before. 

So, I decided to take up the challenge, practice my form, and give it a go for seven days in a row. Here's what happened. 

How to do hanging knee tucks

This bodyweight exercise doesn't require much equipment — just a pull-up bar and a small step if you can't reach the bar from the ground.

But that doesn't mean it's not effective. Hanging knee tucks target abdominal and hip flexor muscle development as well as grip and upper body strength. 

  • You’ll need a pull-up bar for this exercise. If you can’t reach the pull-up bar, use a small step.
  • Grip the bar with palms shoulder-width apart, facing either forward or towards you, depending on which you find more comfortable. 
  • Then, lift your feet off the ground and let your body hang, with your arms locked out. 
  • Drive your knees up, keeping your legs together, to your chest. As you do this, aim to keep your torso sturdy and minimize any swinging by keeping your core engaged. 
  • Lower your legs back down to straight to complete the move before repeating. 

It worked my entire core

If you've tried hanging knee tucks before, you might be used to doing 20 or 30 reps because, naturally, that’s a bit more normal. But 100? Oh my, how my midsection felt the pain.

In fact, many of my hanging knee tucks were done in front of a mirror (I’m not vain; I just can’t help where my gym chooses to place equipment), and I could see my obliques and abs working throughout every rep. 

Obi Vincent, Fitness coach and C4 Energy and Pliability athlete says that hanging knee tucks are especially effective for training the lower abs.

“They can help you achieve the much desired 'V-shape' look.” But there's more to this move than aesthetics alone. 

“Building stronger abs also helps with stability in your core and lower back, allowing you to lift heavier in all movements in the gym and also help to prevent injury," explains Vincent.

My hands felt it the most

Oh, my poor palms. All this gripping onto a bar to do 100 knee tucks really paid its price, and my calluses shone through. To ease the grip pain, I used chalk when it was available. If not, I was taking regular breaks to shake out my hands. My hand moisturizer was overused this week.

It pays to stay engaged

It’s easy to swing around when doing hanging knee tucks, especially if you’re new to the move. I started doing this a lot but firing up that mind-muscle connection makes a world of difference.

Really imagine the core muscles working to keep your body still and ensure that it’s your mid-section helping to drive the knees up to your chest. Move as slowly as you need throughout the move, as this will also help minimize the amount of swinging you do. 

I mixed things up

To make these 100 hanging knee tucks slightly more enjoyable, I turned several into single-leg knee tucks — lifting one knee at a time — and twisted tucks, where I would lift both knees to the right side, and then back to the center before lifting them to the left side.

This really targeted my obliques and kept me far more entertained than abs cycles, another oblique-targeting exercise. If you want to keep strengthening this area outside of hanging tucks, these compound core exercises can help. 

Add a band for ease

Do you struggle to perform hanging knee tucks? Or rather, are you struggling to perform 100 hanging knee tucks? After about 50 or 60 reps, my arms were burning big time, but a resistance band can help.

Vincent explains: “You can add support throughout the exercise, like a resistance band, a partner, or a rack with a back support. This is a great way to increase stability, lessen the strain on the core muscles, and make the exercise easier to perform.”

Making small changes increases the intensity

If you're finding that the hanging knee tuck isn't challenging enough on its own, then well done! But to continue working your muscles, use the progressive overload technique to increase the intensity and add leg raises into the mix. 

Vincent says that leg raises are performed with your legs straight, increasing the lever arm and making the movement more challenging. 

“You can make leg raises harder by slowing the pace, especially on the eccentric (downward) portion of the movement."

"This increases the time under tension, leading to increased muscle hypertrophy. You can even add ankle weights or hold a dumbbell between your feet to further increase the resistance.”

How did I find doing 100 hanging knee tucks every day?

I think this was one of my favorite challenges to date. Not only did I really feel that hanging knee tucks strengthened my core, but they massively worked my arms too, and I noticed increased strength across my body after a week of these hanging knee tucks.

I won't lie; my hands were in tatters, so it might be worth picking up a pair of workout gloves to protect your hands and improve your grip. However, I'm going to add hanging knee tucks into my usual routine, and may even work up to the day when I can do 100 hanging leg raises! 

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Lucy Gornall

Lucy is a freelance health and fitness journalist as well as a pre and post-natal personal trainer. Although a sweaty gym session (skipping rope is a must) is her favorite way to ‘relax’, she’s also a fan of bingeing on The Office, snacking on chocolate-coated raisins, and fizz-filled brunches with friends.