Flexing your spine uses your rectus abdominus muscles at the front of your body and also stretches the erector spinea muscles of your back. Spinal flexion, in which you lean forward and round your back, can be active, such as when performing sit ups or crunches, or passive, as when leaning down to tie your shoe laces. Active movements tend to be initiated by the abdominal muscles, whereas passive movements rely upon gravity and result in stretching of the back muscles. In addition to the exercises below, certain stretches and certain yoga poses involve spinal flexion.
To actively flex your spine, lie on your back with your legs bent and feet flat on the floor. Place your hands on the sides of your head, across your chest or resting on your legs. Lift your shoulders off of the floor by contracting your abdominals and flexing your spine. Pause for a second with your abdominals fully contracted before lowering back to the ground and repeating.
Stability Ball Crunches
This exercise actively flexes your spine starting from a position of slight extension. Sit on a stability ball. Walk your feet forward and lean back so that the ball is situated in the natural curve of your lower back. Place your hands on the sides of your head, across your chest or resting on your legs. Your head should be slightly below the level of your hips. Using your abdominal muscles, flex your spine and lift your shoulders and upper back off of the ball. Hold the top position for 1 to 2 seconds before slowly lowering back into the starting position and repeating.
Ab Wheel Roll Outs
Ab wheel roll outs are performed with an ab wheel or a loaded barbell. Kneel on the floor holding the handles of the ab wheel or placing your hands on the middle of the barbell. Place the ab wheel on the floor just in front of your knees. Keep your arms straight and push the bar away from you by extending your hips. Reach out as far as you feel comfortable so that your body is close to the floor and your arms are extended in front of you. Using your abdominals, actively flex your spine and pull the ab wheel back in top your knees. This is an advanced active spinal flexion exercise.
Stability Ball Back Relaxer
Lie face down on a stability ball with your hands and feet on the floor and the ball filling the natural curve of your abdomen. As you exhale, allow gravity to pull your head and hips downwards to passively flex your spine and stretch your back muscles. Continue breathing, focusing on relaxing more and more each time you exhale.
Lying Tuck Stretch
Lie on your back with your feet on the floor and your hands by your sides. Slowly lift your head and legs by holding onto the backs of your thighs and pulling yourself into a tucked position. Although you are using your arms to flex your spine, this is a passive spinal flexion exercise as your abdominals are not being actively used. Hold this position for a few seconds while trying to squeeze into a smaller tuck each time you exhale.