# Zone 2 Training & VO2max: What the Trials Actually Measured

Fitness predicts how long you live better than smoking, type 2 diabetes, or heart disease, but that evidence is observational. The one large randomised trial that put older adults on structured Zone 2 plus 4x4 interval training (Generation 100, 2020) found no benefit on all-cause mortality at five years. The biology behind Zone 2 and the 4x4 protocol is solid. The popular "this adds 10 years" claim has thinner trial backing than the hype suggests.

Here is the honest version. In study after study, your fitness predicts how long you live better than smoking, type 2 diabetes, or heart disease. But the one big trial that put older adults on a real training plan found no survival benefit. This is the read for anyone in Germany, Austria, or Switzerland who is curious about longevity and tired of the hype.

## On this page

- What Zone 2 and VO₂max Actually Are
- Why Fitness Beats Smoking as a Mortality Predictor
- Does Zone 2 Train Mitochondria Better Than HIIT?
- How Do You Actually Train VO₂max? The Norwegian 4×4
- Generation 100: Did Structured Exercise Cut Mortality?
- Peter Attia's Frame: What's Solid, What's Marketing
- How to Actually Train Zone 2 (Without a Lab)
- Where Can You Get a Spiroergometrie in DACH, and What Does It Cost?
- How Accurate Is Wearable VO₂max?
- Is Endurance Training Bad for Your Heart? AFib and Special Populations
- The Honest Summary

## FAQ

- Is Zone 2 better than HIIT for longevity?
- How much does a Spiroergometrie cost in Germany, Austria, or Switzerland?
- Is the VO₂max from my Apple Watch or Garmin accurate?
- How long does it take for VO₂max to improve with training?
- What is a good VO₂max for my age?
- Does Krankenkasse pay for VO₂max testing in Germany?
- Will Zone 2 training cause atrial fibrillation?
- Do I need to do a lactate test or can I just use heart rate?

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_Full guide: https://longevity-china.com/en/guide/zone-2-vo2max-training_

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_Canonical: https://longevity-china.com/en/guide/zone-2-vo2max-training · Part of Longevity Cities · Updated 2026-06-22_