Band Jack Knife Sit-Up

준비 자세

1. 01Anchor a light band low behind you and lie on your back facing away from the anchor.
2. 02Hold the band handles with arms extended overhead so the band has light tension at the start.
3. 03Extend the legs straight along the floor with ankles together.
4. 04Brace lightly and press the lower back toward the floor before the first rep.

수행

1. 01Exhale and fold at the waist, lifting the trunk and both legs at the same time.
2. 02Reach the hands toward the feet as the band tension climbs.
3. 03Meet in a V position with the hips as the hinge point.
4. 04Lower trunk and legs back down under control without letting the band snap you flat.

체크포인트

• -Trunk and legs rise together, not one after the other.
• -The band stays taut through the whole rep.
• -The lower back does not slam into the floor on the way down.
• -Movement comes from the waist, not from yanking with the arms.

흔한 실수

• -Using arm swing to launch the trunk off the floor.
• -Letting the band pull the torso down quickly on the eccentric.
• -Bending the knees heavily to shorten the lever.
• -Holding the breath instead of exhaling into the fold.