Tip: The GHD Sit-Up – Dangerous or Awesome?

This CrossFit favorite is getting more popular. Is it safe and effective? Well, it depends. Here's what you need to know.

"But, But, It's Bad For Your Back!"

Many trainers won't go near the GHD sit-up, often citing the old "bad for the back" worry. The misconception comes from the angle that the full variation creates. To the untrained eye, it looks like overextension of the lumbar spine.

In actuality, this exercise is king for teaching someone how NOT to overextend the lower back with extended hips. It's the ultimate isometric core exercise and one of the best teaching tools for learning bracing and how to use the hips to generate power.

How do you know when you should implement the GHD sit-up? Well, this isn't for a beginner. Quite frankly, you aren't really in need of it until you have mastered the basics of holding a solid plank and side planks, and are proficient at hanging knee raises and standard sit-ups.

Once you have those down, you need to step it up for your body to get an adaptation. Just like your body gets used to certain weights, it also get used to standard core training.

To set up on the GHD, you'll need the footplate a lot closer to the pads than you think. Experiment with a few distances to see which will have your glutes off the pad. It's crucial to make sure your glutes are off so that your lumbar spine doesn't get blocked and overextended when performing the movement... no matter how scary it might feel. Feel free to weigh down other end of the GHD with plates or kettlebells if you're nervous.

  1. Make sure your feet are correctly in the foot holders and the tops of your feet are against the plate. Have slightly bent knees.
  2. Maintain a neutral spine and begin to lower yourself to parallel. Ideally have a spotter to keep you honest with your neutral spine position.
  3. When you reach parallel, extend your knees sharply. Think about trying to "kick the back plate."
  4. In the upright position, add a slight sit-up to finish the movement by touching your toes.
  5. To increase the difficulty you can start to extend one arm above your head at a time for the reps. Be sure to alternate arms.

When you've done this for a few sessions and feel confident, you can start to add the full range of motion by sitting back until your hips extend completely. This should only be performed to full range if you can still maintain a flat back. If you can't do this without lumbar arching then stay with stopping at parallel.

Do not attempt to touch the floor unless the GHD has been adjusted for your height. Instead, stack a few plates up or use a medicine ball for a target.

This is an exercise that you may not feel at the time, but you'll definitely feel for days after, especially if you go for the full range of motion. Try to stick with lower reps when you first begin and build up your volume safely.


  • Week 1: 5 sets of 5 reps
  • Week 2: 5 sets of 8 reps
  • Week 3: 5 sets of 12 reps
  • Week 4: 7 sets of 16 reps
  • Week 5: 8 sets of 20 reps

Once you can perform 8 sets of 20 reps proficiently, then you can start to implement them into workouts.

You may have seen these performed at events like the CrossFit Games with a medicine ball being held and touched to the ground for high reps. Before you try anything like this you have to remember that these are advanced CrossFit athletes who've been training for many years. They tailor their training to be able to cope with the specific demands of the extra weight.

If you get to the stage where you can safely do reps with an additional weight, I still wouldn't recommend high reps or doing them "for time" for the average gym goer.

Tom Morrison is a British weightlifting coach, martial artist, and CrossFit trainer and competitor. Tom works with athletes on prerequisite movement capabilities for optimal strength, performance, and reduced risk of injury.  Follow Tom Morrison on Facebook