Jackknife Sit-ups / Crunch / Toe Touches
- Lie flat on an exercise mat, extending your arms straight back behind your head.
- Fully extend your legs also. This is the start position.
- Bend at your waist and at the same time, raise your legs and arms to meet in a closed jackknife position. Exhale as you do this.
- At this point, your legs should remain fully extended at between 35-45 degrees from the floor.
- Your arms should be fully extended, parallel to your legs.
- Your upper body should be raised off the floor.
- Return to the start position by lowering your arms and legs back to the floor, exhaling as you do so.
Related exercises to discover
Jackknife sit-ups / crunch / toe touches is a gym work out exercise that targets abs and also involves glutes & hip flexors. Refer to the illustration and instructions above for how to perform this exercise correctly. Star planks, stability / swiss / exercise ball rollout and mountain climbers / alternating knee-ins are related exercise that target the same muscle groups as jackknife sit-ups / crunch / toe touches. Visit our directory for more exercises.
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