Leg Extension Crunch (with Stability Ball)

This dynamic exercise targets your quadriceps and abs, using a stability ball to extend your legs and crunch your torso for a strong core.

IntermediateQuadriceps Rectus Abdominis Iliopsoas Obliques Sartorius Stability ball

Movement: Compound
Force: Pull
Per set: 1 min
Rest: 30s

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Description

A core exercise that targets the lower abs by extending the legs and crunching the torso using a stability ball.

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How to do Leg Extension Crunch (with Stability Ball)

01
Setup
Lie supine on a stability ball, positioning it under your lower back, with feet flat on the floor shoulder-width apart and knees bent at 90 degrees.
02
Setup
Place your hands lightly behind your head, supporting your neck without pulling, and extend your legs forward until they are straight and your body forms a straight line from shoulders to heels.
03
Exhale as you simultaneously crunch your torso upward, bringing your rib cage towards your pelvis, and flex your hips and knees to pull your feet back towards your glutes.
04
Focus on contracting your rectus abdominis and quadriceps as you bring your knees in and lift your shoulders off the ball.
05
Inhale as you slowly and controlledly reverse the movement, extending your legs back to the straight position and lowering your torso back onto the stability ball.
06
Fully extend your legs and torso to the starting position before initiating the next repetition, maintaining core engagement throughout the entire movement.

Tips

Maintain a neutral neck position throughout the crunch by looking towards the ceiling or slightly forward, avoiding strain on your cervical spine.
Control the movement both on the way up and down; avoid using momentum to swing your legs or torso, focusing on deliberate muscle contraction.
Engage your core before you start the movement by drawing your navel towards your spine to protect your lower back and maximize abdominal activation.
Adjust the stability ball position to find the sweet spot for your lower back; it should support you without causing discomfort or instability.

Common mistakes

Using momentum to crunch or extend: Focus on slow, controlled movements, especially during the eccentric (lowering/extending) phase, to maximize muscle engagement.
Pulling on your neck during the crunch: Keep your hands light behind your head and initiate the crunch from your core, not by yanking your head forward.
Losing balance on the stability ball: Engage your glutes and core to stabilize your body on the ball, ensuring a controlled and safe movement.

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Questions

What muscles does Leg Extension Crunch (with Stability Ball) work?

Leg Extension Crunch (with Stability Ball) primarily targets Quadriceps, Rectus Abdominis. Secondary muscles include Iliopsoas, Obliques, Sartorius.

Is Leg Extension Crunch (with Stability Ball) good for beginners?

Leg Extension Crunch (with Stability Ball) is rated intermediate. Beginners can still attempt it with lighter weight and careful form, but it's best to master easier variations first.

What equipment do I need for Leg Extension Crunch (with Stability Ball)?

You need Stability ball to perform Leg Extension Crunch (with Stability Ball). If you don't have this equipment, look for variations that target the same muscles with what you have available.

What are the best tips for Leg Extension Crunch (with Stability Ball)?

Maintain a neutral neck position throughout the crunch by looking towards the ceiling or slightly forward, avoiding strain on your cervical spine. Control the movement both on the way up and down; avoid using momentum to swing your legs or torso, focusing on deliberate muscle contraction. Engage your core before you start the movement by drawing your navel towards your spine to protect your lower back and maximize abdominal activation. Adjust the stability ball position to find the sweet spot for your lower back; it should support you without causing discomfort or instability.

What are common mistakes when doing Leg Extension Crunch (with Stability Ball)?

Using momentum to crunch or extend: Focus on slow, controlled movements, especially during the eccentric (lowering/extending) phase, to maximize muscle engagement. Pulling on your neck during the crunch: Keep your hands light behind your head and initiate the crunch from your core, not by yanking your head forward. Losing balance on the stability ball: Engage your glutes and core to stabilize your body on the ball, ensuring a controlled and safe movement.