Field

Measurement

The numbers used to describe ageing, and how much each one is worth.

• Blue ZonesmixedRegions reported to have exceptional longevity, and the data-quality problem underneath them.
• FrailtygoodA measurable loss of physiological reserve. Not a synonym for age.
• Grip strengthgoodA five-second test that predicts a lot. Train the body, not the grip.
• Lifespan vs. healthspangoodYears alive versus years in good health. The gap between them is the thing worth shrinking.
• VO2 max and cardiorespiratory fitnessgoodAerobic capacity. Strongly predictive, genuinely trainable, rarely measured.

← Full index