Drop in all-cause mortality per one-MET gain in — no ceiling observed.
A retrospective cohort of 122,007 adults undergoing treadmill testing found every one-MET increase in cardiorespiratory fitness cut all-cause mortality by 10–25%, with no upper ceiling — elite fitness carried the lowest risk.
What the researchers did
Mandsager and colleagues at the Cleveland Clinic followed 122,000 adults for a median 8.4 years after direct treadmill testing, stratifying mortality risk by fitness percentile.
The key finding
Low fitness (bottom 25%) carried roughly 4–5× the mortality risk of elite fitness (top 2.5%) — a bigger effect than smoking, diabetes and end-stage kidney disease. There was no plateau. Going from 'below average' to 'above average' halved mortality.
Why it matters
is the strongest single predictor of longevity we can meaningfully train. volume builds the base; short push the ceiling.
Train as if your life depends on it. It largely does.
- 1.6–2.2Daily protein intake that maximises hypertrophy.
- 7–9Nightly sleep for recovery, hormones and growth hormone release.
- 8,000Daily step count where all-cause mortality risk levels off — largely a NEAT effect.
- 3–5Creatine monohydrate dose — no loading needed.
- 3–6Pre-training caffeine dose that reliably improves strength and endurance output.
- 25–38Daily fibre intake linked to lower all-cause mortality and a healthier gut microbiome.