What is Zone 2?

The short answer

Zone 2 is a heart-rate range, usually defined as roughly 60 to 70 percent of your maximum heart rate. In practice it looks a lot like easy pace: comfortable, conversational, sustainable for a long time.

If you do not use a heart-rate monitor, you can find Zone 2 with the talk test. Full sentences, steady breathing, no urge to speed up. That is the zone.

Where the zones come from

Training zones are a way of describing how hard you are working. They are usually built from either heart rate or lactate testing. The boundaries differ slightly between systems, which is why two runners can both say "Zone 2" and mean slightly different efforts.

For everyday training you do not need a lab test. The useful distinction is simple: easy work that builds endurance, moderate work that is too hard to recover from quickly, and genuinely hard work that sharpens speed.

The zone is a guide, not a scoreboard. If you feel good and the effort is conversational, you are in the right place.

Why runners talk about it so much

Zone 2 training builds the aerobic base: the heart, blood vessels, and mitochondria that determine how long you can keep going. It is low-stress enough to do often, which is exactly why it works – frequency matters more than intensity for base building.

It is also the easiest way to avoid the middle ground. Runners who push every run to a moderate effort get most of the fatigue of hard training with little of the benefit.

Putting it into a normal week

Most recreational runners can do the majority of their weekly running in Zone 2 and add one or two harder sessions. A typical week: three or four easy Zone 2 runs, one tempo or interval session, and one longer run that stays mostly easy.

Heart rate drifts upward with heat, caffeine, stress and dehydration. If your heart rate says Zone 3 but the effort feels conversational, trust the effort.

Beginner

All running can be Zone 2 for the first few months.

Regular runner

70–80% of weekly time in Zone 2, plus one or two hard sessions.

Racing

Keep the base; let the hard sessions get more specific to your goal.

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