Equipmentbody weight
Difficultyintermediate
abswaist
Jackknife Sit-Up
The jackknife sit-up is a bodyweight exercise targeting the abdominal muscles. It involves simultaneously lifting the legs and upper body to meet in the middle, engaging the core and hip flexors.
Step-by-Step Form & Technique
- 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.
Secondary Muscles
hip flexors
Track Jackknife Sit-Up in RepEight
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