Question 1

What is Zone 2 training?

Accepted Answer

Zone 2 is the aerobic training zone where your body uses fat as its primary fuel source and your cardiovascular system is working at a sustainable, conversational pace. It's typically 60–72% of your maximum heart rate, or more precisely calculated using the Maffetone Method (180 minus your age, with adjustments). At this intensity, you should be able to speak in full sentences — if you're gasping, you've gone too hard.

Question 2

Why is Zone 2 important for longevity?

Accepted Answer

Zone 2 training is the most powerful stimulus for mitochondrial biogenesis — growing new mitochondria in your muscle cells. More mitochondria means better fat oxidation, metabolic flexibility, and cellular energy production. Research shows Zone 2 training reduces cardiovascular disease risk, improves insulin sensitivity, and is associated with significantly lower all-cause mortality. Dr Peter Attia calls it 'the most important type of exercise for longevity.'

Question 3

What is the Maffetone Method?

Accepted Answer

The Maffetone Method, developed by Dr Phil Maffetone, calculates your aerobic threshold heart rate as 180 minus your age, with adjustments: subtract 10 if recovering from illness, subtract 5 if you're a returning exerciser, add 5 if you're an experienced competitive athlete with no health issues. This gives you the upper limit of Zone 2 — your aerobic threshold, the point where fat burning is maximised without tipping into glycolytic (sugar-burning) exercise.

Question 4

How much Zone 2 should I do per week?

Accepted Answer

Research and elite coaches (including Inigo San Millan, who works with Tour de France cyclists) recommend 80% of all cardio training be in Zone 2, with only 20% in higher zones. For recreational athletes, that means 3–5 sessions of 30–90 minutes per week. Beginners should start with 20–30 minutes and build gradually. The benefits compound over months — don't expect immediate performance improvements.

Question 5

What's the difference between Zone 2 and the fat-burning zone?

Accepted Answer

These terms are sometimes used interchangeably but have different definitions depending on the source. The old '60–70% of max HR fat-burning zone' from gym equipment is often too low. The true aerobic threshold (Zone 2 in the 5-zone model, or Zone 1 in some 3-zone models) is best determined by the Maffetone Method or a lactate threshold test, as it varies significantly by individual fitness level.

Zone 2 Heart Rate Calculator

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