To Tuck or not to tuck? That is the question.
And just like for Hamlet, there is no easy answer. It’s all in your relation to gravity, what movement you are performing, and what kind of weaknesses and spinal posture you have right now.
When performing exercises on your back that require spinal stabilization – keeping the back still while moving the arms and legs – it is important to learn how to maintain a neutral pelvis and spine. We want to strengthen the natural alignment without force.
To find neutral pelvis, first learn how to isolate and move the pelvic bones by doing pelvic tilts.
Lying on the back with knees bent, draw the pelvic bones inward towards your nose, pressing the low back into the floor and slightly lifting the tailbone off the floor. This is called tucking under. Next, go the opposite direction, creating a tunnel or arch with the low back by drawing the pelvic bones downward towards the knees, tailbone connects to floor. This is called arching.
Neutral pelvis is the happy medium between this range of motion. The front two pelvic bones are pointing upward towards the ceiling, most likely creating a slight arch in the low back.The tailbone and the back of the rib cage remain heavy on the floor. To engage the abdominals in this neutral pelvis, imaging trying to zip up the last bit of zipper on your tightest pair of pants! The muscles between the pelvic bones should sink down, but the bones themselves should not move.
(Refer to the picture at the top of the post)
Exercising supine (lying on your back) maintaining neutral pelvis will strengthen and stabilize the spine, allowing the arms and legs to move around freely. Your abdominals gather towards the spine ( like a corset closing in on all sides of the waist, belly and back), but, don’t force down the belly by tucking under the pelvis. Often we confuse scooping the abdominals with tucking under the pelvis. This will only create bad spinal stability habits in the long run, leading to overdeveloped hip flexor muscles, weak core, and an overstretched low back. The tuck under for stability when lying down will translate to a lordotic low back when standing, or what is called “sway back”.
There are always exceptions to every rule. If your back is extremely weak or you have never exercised then modifications must be made. Prop up the pelvis with a small pillow or blanket roll to support weak back muscles when lying on the back. This elevation of the backside will create less pressure directly on the spine and allow you to feel the core muscles. In this case, DO work on keeping the low back heavy and the pelvis tucked under. Given the body’s change in relation to gravity and weakness of the muscles, this works best. As one gets stronger take the prop away and work in neutral pelvis.
Once you’ve found a neutral pelvis position, practice moving the arms and legs while maintaining the stable spinal column.
A good image to help create stabilization would be to imagine balancing a bowl of water ( or a glass of champagne, depending on your preference) on top of the pelvis, just below the navel and between the pelvic bones.
For a more difficult stability challenge, try balancing a tennis ball or golf ball on this same low point in the torso.
Good luck. Once you are able to maintain and understand a correct neutral position, it is surprising how fast one can strengthen their body from the center outward!