Exercise technique

flexion leg sit up (bent knee)

The flexion leg sit up (bent knee) is an abdominal exercise performed with body weight. It involves curling the upper body and bringing the knees toward the chest simultaneously, targeting the abs and hip flexors.

Open this exercise in STARK Download on the App Store

How do you perform this exercise?

  1. Lie flat on your back with your knees bent and feet flat on the ground.
  2. Place your hands behind your head with your elbows pointing outwards.
  3. Engaging your abs, slowly lift your upper body off the ground, curling forward until your torso is at a 45-degree angle.
  4. At the same time, lift your legs off the ground, bending your knees and bringing them towards your chest.
  5. Pause for a moment at the top, then slowly lower your upper body and legs back down to the starting position.
  6. Repeat for the desired number of repetitions.

Which other muscles are involved?

Hip flexors.

How do you log your sets?

How do you track progressive overload?

Source: ExerciseDB catalogue and demonstration. Related movements are options to compare, not equivalent loads or a prescribed progression.

Alternatives to explore

band jack knife sit-up

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flexion leg sit up (straight arm)

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jackknife sit-up

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sit-up v. 2

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half sit-up (male)

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assisted sit-up

Abs · Assisted

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