If the safest way to deadlift is with a neutral spine, why is it that the worlds best dead lifters in history lift with a rounded back? They found that this position is the one that allows them to pull the greatest load, and also to be pretty safe and stable. People get self conscious when they realize they can lift heavier with a rounded back, and automatically assume their bodies are dysfunctional. More often than not, this isn’t the case. This discussion has nothing to do with optimal spine health, its simply about techniques utilized to lift the most weight, safely.
With a neutral spine posture, you rely mostly on your back extensors (erector spinae, multifidi, QL) to keep your spine stabilized and maintain the arches. But if you slightly round your back, you get both active and passive support. So the misconception that the spine is not stable in a round position is completely flawed. The spine does indeed stabilize in a rounded position.
In a neutral position stability comes from your elector spinae, intra abdominal pressure, and muscles surrounding the core like the rectus abdominis and obliques, which when they contract they actually produce a flexion torque, meaning that they encourage a rounding back.
If you SLIGHTLY round your upper back you get active plus passive support. The thoracolumbar fascia surrounds the muscles in the core and around the back. When the erector spinae and latissimus dorsi muscles contract they stretch out this fascia and aid in stability of the spine. The activity of the abdominal muscles naturally pull the spine and the core into slight flexion. Lastly the spinal ligaments are also more taut with the back in slight flexion.
It is important to consider the use of the word “SLIGHT”. Slight flexion implies flexing the spine a few degrees, while always avoiding end range flexion.
In conclusion, the majority of contribution in the rounded back deadlift comes mostly from active muscle contraction, but doing so allows the passive structures to also generate stability, and this is what allows us to lift heavier loads, safely. Spinal extensors are stronger in flexion, and the increased intra abdominal pressure and core strength in this position help prevent the spine from flexing too far forward, thus protecting it from injury.
Stay tuned for Part II: Good vs. Bad Rounded back deadlift