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All exercises

Flexion leg sit up (bent knee)

Intermediate

Flexion leg sit up (bent knee) is a isolation bodyweight exercise for the abs, also working the quads.

What it works

Primary muscle

Abs

Also works

Quads

Equipment
Bodyweight
Movement
Core
Type
Isolation
Logged as
Reps
Suggested rest
1 min

How to do it

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

What to do instead

  • Band jack knife sit-upResistance band
  • Flexion leg sit up (straight arm)Bodyweight
  • Jackknife sit-upBodyweight
  • Sit-upBodyweight
  • Half sit-upBodyweight
  • Assisted sit-upMachine

Easier variations

  • Assisted sit-upMachine
  • 3/4 sit-upBodyweight
  • Half sit-upBodyweight
  • Prisoner half sit-upBodyweight

Harder variations

  • Janda sit-upBodyweight
  • Weighted decline sit-upWeight plate
  • Decline sit-upBodyweight
  • Band jack knife sit-upResistance band
Logged today · 1 min restFlexion leg sit up (bent knee)

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