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jackknife sit-up

jackknife sit-up exercise guide with muscles, equipment, animation and step-by-step instructions. Target: abs. Equipment: body weight.

jackknife sit-up exercise demonstration
Target muscle
abs
Muscle group
hip flexors
Body part
waist
Equipment
body weight

Secondary muscles

hip flexors

How to perform

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