Lie supine with knees bent, feet hip-width, arms relaxed by sides.
Inhale to prepare, exhale and posteriorly tilt pelvis.
Roll spine up one vertebra at a time into bridge.
Press through legs until legs are nearly extended. Lower back to start.
Then begin rolling your spine downward until your back is flat against the carriage.
Вращения бедрами 运动指南 - Поясница 锻炼 | MuscleWiki