
01
The Struggle
Late winter on the Mississippi felt like rowing through glass, beautiful, unforgiving. Caleb Whitaker watched his athletes glide while his own test pieces cratered. His VO₂ max had fallen from 56 to 48 mL/kg/min in a year. Post-COVID, he never quite recovered; intervals left him heaving, hands cold, lips pale. Resting O₂ sat dipped to 94–95% after hard days. Overtraining? Maybe. But he trained less and still felt slow.

02
The Breaking Point
During a 2k erg demo, his vision dotted black at 1200 meters. He stopped, in front of his novices. Shame burned hotter than his quads. That night he searched low vo2 endothelial nitric oxide and found Vitals Vault. “Oxygen & Circulation, assess erythrocytes, iron kinetics, and endothelial signaling.” It sounded like the missing half of the equation.

03
The Discovery








