The concept of neutral spine sounds easy. You maintain the natural curves of your spine while doing an exercise – like an upper abdominal curl. Keeping neutral means the muscles in your back will be working along with your abs and when you get your abs and back to fire together you are working your core. Also, it is more difficult to recruit your leg muscles to help you cheat when you maintain neutral spine during ab work.
The concept sound simple, natural even, but when the majority of people lie down on their backs to exercise they automatically and immediately press their low spines into the floor. This, my friends, is not neutral.
So how to find neutral?
- Lie down on your back with your knees bent and your feet flat on the floor, with your heels about a foot from your bum.
- Rock your pelvis up and down so you can feel the top and bottom of your sacrum [1] - the back of your pelvis.
- Stop rocking and feel the entire sacrum on the ground, allowing the 5 vertebrae in your lumbar spine to make a gentle curve away from the floor. It is not a big curve!
- Your bottom rib should also be making contact with the floor.
- The curve of your neck should mirror the curve of your low spine, so it pulls away from the floor as well.
To learn how to find neutral spine from the front just
You can also approach figuring neutral spine from the front.
- Your pubic bone and top of your pelvis (ASIS [2]) should be in the same plane and parallel to the floor.
- To get a sense if these bones are even, place the heels of your palm on the top of your pelvis and the middle finger, of both hands on your pubic bone. These bones should be on the same plane.
- The apex of the curve in your lower (lumbar) spine, should be even with your belly button. This is another way to feel that the curve is there, but not huge!
Fit's Tip: When lying on your back with both feet off the ground, you should round your low back (super scoop) and not maintain neutral. In those positions (like the 100's in Pilates), rounding the spine protects your back!
Source [3]