Sit tall with legs extended, arms holding straps at chest height.
Rotate torso slightly, engaging obliques as you begin rolling back.
Maintain rotation and bend elbows, keeping shoulders relaxed and spine controlled.
Roll back up with control, returning to center without losing tension.
背部划船预备:侧腹卷背下放エクササイズガイド - 腹斜肌ワークアウト | MuscleWiki