How To Do The Double Crunch Properly

The double crunch is a highly effective ab exercise that combines the features of the traditional abdominal crunch and the reverse crunch for an extensive core workout.

It is an effective way to work the entire length of your abdomen and hip flexors without needing any special equipment.

This exercise is relatively easy to do; you only need to follow these simple steps:

  • Lie on your back on the floor with your feet flat and your knees bent.
  • Place your hands alongside your head, making sure your fingers are gently touching your temples.
  • Tighten your core to engage your core muscles and flatten your lower back gently on the floor. This is your starting position.
  • Slowly, raise both knees until your thighs are at a 90-degree angle with the ground.
  • As you raise the knees, lift your shoulders and head off the floor.
  • Move your chest upward until it slightly touches your knees. At the top position, your forehead and knees should be about 6 inches apart.
  • Reverse these steps until your back and shoulders are on the ground, and your feet are flat on the floor.
  • Do 3 sets of 10-15 reps each.


The double crunch mainly targets your rectus femoris, rectus abdominis and both the internal and external obliques.

It also works the muscles on your legs, hips, shoulders and arms as you extend them to touch your temples.



The double crunch isolates and strengthens your entire core musculature, from the rectus abdominis at the top of your abdomen to the external obliques at the sides.


This exercise requires zero equipment to execute, only a good form and your bodyweight.

However, you can use a yoga mat or any other soft surface for additional comfort.


Developing stronger core muscles helps support and stabilize your spine hence improving your posture.



If you can access dumbbells, this exercise would be a fantastic way to increase external resistance and make the basic double crunch more challenging.

It is quite similar to the double crunch, except in this case you place and hold a dumbbell between your feet as you perform the movement.


  • Sit on the floor with your knees bent and both feet on the floor.
  • Place a dumbbell between your feet. The dumbbell should be perpendicular to the length of each of your feet.
  • The weighted part of the dumbbell should be resting on top of your feet.
  • Lie on your back and place both hands alongside your head. Gently touch your temples with your fingers to prevent them from moving.
  • Tighten your core and keep your lower back flat on the floor. You can try visualizing your ribs moving toward your pelvis to keep the core tight throughout the exercise.
  • Lift your shoulders and head off the floor, and then raise the chest toward your knees.
  • As you raise your upper back and shoulders off the floor, lift the feet and the dumbbell off the floor too.
  • Bring the knees towards your chest and keep your feet pressed together to prevent the dumbbell from moving.
  • Reverse these steps until your upper back and shoulders are on the floor again.
  • Do 3 sets of 10-15 reps each.


The V-up is an advanced variation of the crunch that is ideal for people who are looking to make the standard crunch a bit more challenging.

The basic mechanics are quite similar, but in the v-up your arms and legs remain straight from the beginning of the exercise to the end.

How to do it:

  • Lie on your back on the floor.
  • Extend your arms overhead and straighten your legs.
  • Raise your legs and arms about 6-12 inches off the floor.
  • Tighten your core by flexing the abdominal muscles and moving your ribs toward your pelvis. Your lower back should be flat on the floor.
  • Squeeze your thighs and feet together.
  • Slowly and with control, raise your torso and legs and reach out for your toes with both hands.
  • At the top of the rep, your legs and torso should form a “V” shape. Don’t worry if you are unable to reach your toes – you can instead just get as close to them as you can.
  • Slowly, reverse these steps until your back is on the floor and your arms are overhead again.
  • Perform 3 sets of 6-12 reps each.



Arching your lower back deactivates your rectus abdominis and focuses on your hip flexors instead.

This position may strain your lower back and put it at risk of injury, according to research.

To avoid arching your back, make sure you are properly bracing your core at the starting position.

If you feel too tired to keep bracing your core, stop the set immediately and rest for a while before continuing.


It is common to find beginners placing their hands behind their heads and compressing their chins toward the chest.

This position strains your neck and may make it difficult for you to breathe.

To avoid the temptation of crunching your neck, make sure you place your hands alongside your head or cross your arms on your chest.


The double crunch is a fantastic way to work a wide range of muscles in your trunk and core.

What’s even better, it requires no equipment to perform and you can easily adjust the difficulty level to make it easier if you find it too challenging or more difficult if you find it too simple.

Note that this exercise activates the hip flexors, which could trigger lower back pain in people with back issues.

Therefore, if you struggle with lower back pain, consider doing alternative ab exercise that will not strain your back.

For other healthy individuals, the double crunch is a great addition to your core workout routine.