jackknife sit-up
Body part:
waist
Equipment:
body weight
Body target:
abs
Secondary muscles:
- hip flexors
Instructions:
- 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.