Crunch

Muscles Crunch Works

Main muscleLie on your back, raise your legs, and slightly curl your pelvis up. The main muscle driving this movement is your rectus abdominis. Your abs contract to posteriorly tilt your pelvis and tighten the lower-ab area.

Supporting musclesYour hip flexors help lift your legs, and your obliques help keep your torso from rocking side to side.

How it should feelAs your legs rise and your tailbone curls slightly off the floor, your lower abs should squeeze hard. As you lower, keep tension in your abs so your lower back does not arch.

Signs you're offIf your lower back lifts off the floor or you swing your legs, you are using hip flexors and momentum more than your abs. If your neck and shoulders tense up, your upper body is working too hard.

Remember thisFocus on curling your tailbone up slightly and squeezing your lower abs, not just lifting your legs.

Muscles used

• Rectus abdoministhe front abs, commonly called the six-pack
• Hip flexorsmuscles at the front of the hip that help lift the thigh
• Obliquesside abs running from the ribs toward the pelvis

Setting Up for Crunch

Setup orderLay down a long mat

• Mat

  Set it like thisLay down a Mat long enough to reach from your head to your hips when you lie down.

  How to checkWhen lying down, your back and buttocks must be on the Mat, and the Mat must not slide on the floor.

Watch out forThe Mat is short, so Avoid starting with your back or buttocks touch the floor.

Stance for Crunch

Foot widthLie on the mat with your knees bent and both feet comfortably on the floor.

Where your weight goesKeep your hips and feet on the floor so your body does not slide.

Upper body positionPlace your hands beside your head or in front of your chest.

Why it mattersIf your feet are unstable, your body may shift as you curl your upper body up.

How to Grip for Crunch

Grip typeDo not hold any handles or equipment; lightly place your fingertips beside your temples.

Grip widthPlace both hands in the same position beside your face.

How hard to gripDo not tense your fingers, and do not let your wrists bend.

The Key Point for Crunch

Without pulling your neck, curl your upper body slightly upward so that the space between your ribs and pelvis becomes closer.

Think of it like thisThe feeling of folding the front of the belly short

Before the fixI tense my neck and shoulders and try to lift my upper body high.

After the fixIt strengthens the upper abdomen and reduces strain on the neck.