Glute-Ham Developer Crunch

Muscles worked

Setup

1. Adjust the GHD footplate so that your glutes are hanging slightly off the back of the seat pad.
2. Secure your feet firmly between the rollers with your knees slightly bent.
3. Sit upright with your torso vertical and cross your arms over your chest or hold them by your ears.

How to do it

1. Inhale and slowly lower your torso backward until your body is parallel to the floor or slightly below, maintaining a neutral spine.
2. Exhale sharply and explosively contract your abdominals and hip flexors to return to the starting upright position.
3. As you rise, focus on 'firing' your quads to pull your torso up through the foot anchors.
4. Maintain a controlled 2-second eccentric (lowering) phase and a powerful 1-second concentric (rising) phase.

Form checklist

• Keep a slight bend in the knees throughout the movement to protect the lower back.
• Avoid excessive arching of the lumbar spine at the bottom of the range.
• Ensure your hips are positioned just behind the peak of the pad to allow for full spinal extension.
• Keep your chin tucked slightly to maintain a neutral neck alignment.

Pro tips

• Focus on the 'knee snap'—actively trying to straighten your legs against the rollers—to recruit the rectus femoris and accelerate the upward phase.
• Visualize pulling your ribcage toward your pelvis rather than just hinging at the hips for better abdominal recruitment.

Make it harder

• Hold a weight plate or medicine ball against your chest or extended overhead.
• Increase the range of motion by lowering your torso until your hands touch the floor behind the machine.

Frequently asked

What muscles does the glute-ham developer crunch work?

The glute-ham developer crunch primarily targets the abs and obliques, and also works the glutes and hamstrings as secondary muscles.

What equipment do you need for the glute-ham developer crunch?

The glute-ham developer crunch requires no equipment — just your body weight.

Is the glute-ham developer crunch good for beginners?

The glute-ham developer crunch is rated advanced. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

• 3/4 Sit-UpBeginner · abs and obliques
• 45 Degree Bicycle Twisting CrunchIntermediate · abs and obliques
• 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
• 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals