The First to Fall: Fast Motor Units as the Hidden Trigger of Human Aging

This paper offers a fresh perspective on human aging, one that begins not at the cellular level, but higher up—at the connection between brain and muscle. We argue that the slow, steady loss of fast motor units starting in our late twenties isn’t a symptom of aging, but the very spark that sets it off. Instead of blaming telomeres, mitochondria, or DNA damage as the root causes, we suggest these are downstream effects—unleashed only after the nervous system begins to pull back its control. Drawing from neuroscience, elite athletic data, and logic, we propose that defending neuromuscular function—not just repairing cells—may hold the key to extending youth and delaying systemic breakdown.