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All exercises

Band jack knife sit-up

Intermediate

Band jack knife sit-up is a isolation resistance band exercise for the abs, also working the quads.

What it works

Primary muscle

Abs

Also works

Quads

Equipment
Resistance band
Movement
Core
Type
Isolation
Logged as
Weight × reps
Suggested rest
90 seconds

How to do it

  1. 1Lie flat on your back with your legs straight and your arms extended overhead, holding the band.
  2. 2Engage your abs and lift your legs and upper body simultaneously, bringing your hands towards your feet.
  3. 3Pause for a moment at the top, then slowly lower your legs and upper body back down to the starting position.
  4. 4Repeat for the desired number of repetitions.

What to do instead

  • Sit-upBodyweight
  • Decline sit-upBodyweight
  • Jackknife sit-upBodyweight
  • Half sit-upBodyweight
  • Assisted sit-upMachine
  • Band push sit-upResistance band

Easier variations

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

Harder variations

  • Janda sit-upBodyweight
  • Weighted decline sit-upWeight plate
Logged today · 90 seconds restBand jack knife sit-up

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