Jackknife Sit-Up
10 reps
Fold up like a jackknife, lifting straight legs and torso to meet in the middle.
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ABS
Jackknife Sit-Up
This move brings a full sit-up together with a leg raise so your body folds shut at the hips. Since your entire torso lifts along with your legs, it demands more from the core than a shoulders-only crunch.
How to do it
- 1
Lie on your back with legs straight and arms extended overhead on the floor.
- 2
Tilt your pelvis to press your lower back into the floor.
- 3
Bend at the hips to lift your straight legs while curling your upper back off the floor.
- 4
Let your arms travel with you so they end up parallel to your raised legs at about 45 degrees.
- 5
Lower back to the starting position under control, keeping tension in your abs.