Training Insights

Peter Attia on Zone 2 and Zone 5 Training

By Dr. Rick Cohen • Updated September 8, 2025

The overall take away from this article is that you don't need to kill yourself everyday on the bike, treadmill, or weight machines. The correct balance of exercise and physical activity should be slow and easy most of the time and then hard and fast for less of the time. This is how to achieve optimal health, fitness, and longevity benefits. You may also find topics such as the fitness pyramid, the better food pyramid.

Zone 1 is 50-60% HRM (Heart Rate Max), Zone 2 is 60%-70% HRM, and Zone 5 is 90-100% HRM. You don't have to use a lactate meter to know you are doing Zone 2, a simple heart rate monitor or subjective check-in to your effort expenditure is plenty; the point is to go hard enough to where you feel like you need to increase breathing but not feel terrible burn or no burn at all; a pace you can sustain for a few hours, but with some effort. As for zone 5 training, don't worry about spending hours in this zone, more like seconds. The key is to push yourself hard every now and then, preferably keep these hard pushes under 1 minute with plenty of recovery time in-between; sprinting or some really hard exercise type either on land, bike, or in the water is what you are looking for here.

How do you calculate your HRM? A simple 220 minus your age is a great way to judge your HRM. This means Zone 1 for a 40 year old should be around 90BPM to 108, something you could achieve with some upbeat gardening or medium paced walking around the block.


Everything Peter is talking about in terms of exercise is about optimizing for longevity.

That is much different than optimizing for performance.

For instance, if someone were to want to run the fastest 10k possible…

That means training at an energy system that is very demanding of the cardiovascular system. It is pretty much maximum cardiac output just beneath VO₂ max above functional threshold, which is past the point of optimizing longevity returns and it actually comes at some cost to longevity relative to something more at a slightly lower energy system.

Instead, Peter thinks about training for the Centenarian Decathlon ⇒ i.e., being a kickass 90-year-old.

The main energy systems of life

  • Zone 1
  • Zone 2
  • Zone 5

“By training zone 2 and zone 5 . . . we’re really teeing ourselves up metabolically and also structurally to do these things.”

Exercise components — Zone 2 and Zone 5 training

Zone 2 training

Make sure to check out the podcast with Iñigo San Millán.

Iñigo explains that zone 2 is basically the highest level of exertion that is effectively pure mitochondrial oxidative phosphorylation before you start to net accumulate lactate (PubMed reference).

How Peter does Zone 2 training:

  • Peter does zone 2 about four times per week
  • He uses a lactate meter to make sure he is right on that limit of not going too far, not pushing too hard, but pushing hard enough
  • Usually he does it on a stationary bike hooked up to a power meter, titrating watts and heart rate until lactate is ~1.8–1.9 mmol
  • If on a treadmill: 15% incline, ~3.0–3.4 mph
  • Can also be done on an elliptical

What is the right dose of Zone 2?

  • Beginner: ~2 hours per week
  • Ideally: 3–4 hours per week

Peter notes you probably can’t do too much Zone 2 — the limit is mostly time allocation versus other training forms.

Zone 5 training

Zone 5 is high intensity (i.e., HIIT) and the fourth and final piece of exercise. You don’t need to spend much time in Zone 5, but neglecting it completely has a cost, says Peter.

He uses the analogy of an escalator being broken, and you’re late for your flight with luggage and a child — that’s Zone 5 training.

HIIT vs aerobic exercise

Many studies compare HIIT to aerobic exercise on a minute-for-minute basis (Harvard Health). HIIT is more efficient when measured this way. But Peter does not view it as either/or. Using both is optimal — and Zone 5 doesn’t require much more time commitment.

Peter Attia’s weekly exercise routine

  • 3–5 bouts of strength training
  • 4 bouts of Zone 2
  • 2 bouts of Zone 5
  • Stability sprinkled daily, with one longer 60-minute session per week

Supplements to support Zone training

Zone 2 and Zone 5 performance can be further supported by:


Continue exploring: More longevity and training articles

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