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Chapter 2: Standing Up

Walking upright was the most consequential decision in human history -- not the brain, not language. And your lower back is still paying for it 6 million years later.

Key Insights

80% of humans experience lower back pain because the spine was retrofitted from a horizontal bridge to a vertical column

200,000 ACL tears per year in the US alone -- quadrupeds don't have this problem because they spread weight across four joints

Standing upright reduced solar heat gain by 60%, turning humans into the most efficient heat-dissipating organisms on the planet

Your body has 26 anatomical features that serve no purpose in walking but are critical for running -- you were born to run, not sit

Physical inactivity kills 5.3 million people per year worldwide -- on par with smoking

Read the full chapter to learn why the restlessness you feel after 8 hours at a desk is 2 million years of engineering telling you to move.

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