
jackknife sit-up
- Body Part
- Waist
- Equipment
- Body Weight
- Target Muscle
- Abs
- Secondary Muscles
- hip flexors
How to do it
- Lie flat on your back with your legs extended and your arms overhead.
- Engage your core and lift your legs and upper body simultaneously, reaching your hands towards your toes.
- Pause for a moment at the top, then slowly lower your legs and upper body back down to the starting position.
- Repeat for the desired number of repetitions.





