The exercise ground crunch primarily works the muscles Abdominals and secondarily works the muscles .

Proper position Lie down on the floor. Knees bent and feet flat on the floor. Cross your arms around your shoulders. Belly tucked in. Movement and breathing Exhale, contracting your abdominal muscles as you raise your torso. Inhale as you bring your shoulders to the floor.

Proper position Lie down on the floor. Knees bent and feet flat on the floor. Cross your arms around your shoulders. Belly tucked in. Movement and breathing Exhale, contracting your abdominal muscles as you raise your torso. Inhale as you bring your shoulders to the floor.